Home-immediately access 800+ free online publications. Download CD3WD (680 Megabytes) and distribute it to the 3rd World. CD3WD is a 3rd World Development private-sector initiative, mastered by Software Developer Alex Weir and hosted by GNUveau_Networks (From globally distributed organizations, to supercomputers, to a small home server, if it's Linux, we know it.)ar.cn.de.en.es.fr.id.it.ph.po.ru.sw

CLOSE THIS BOOKAppropriate Building Materials: a Catalogue of Potential Solutions (SKAT, 1988, 430 p.)
Examples of building systems
VIEW THE DOCUMENTMud brick vaults and domes
VIEW THE DOCUMENTEarthquake resistant mud/bamboo structures
VIEW THE DOCUMENTAdobe brick house
VIEW THE DOCUMENTModular framed earth block construction
VIEW THE DOCUMENTLok Bild system
VIEW THE DOCUMENTConcrete panel house
VIEW THE DOCUMENTFerrocement housing units
VIEW THE DOCUMENTFibracreto building system
VIEW THE DOCUMENTBamboocrete construction
VIEW THE DOCUMENTBamboo houses
VIEW THE DOCUMENTPrefabricated timber hut
VIEW THE DOCUMENTPrefabricated wooden house
VIEW THE DOCUMENTTimber houses for flood areas
VIEW THE DOCUMENTRha-lime prototype house

Appropriate Building Materials: a Catalogue of Potential Solutions (SKAT, 1988, 430 p.)

Examples of building systems

Mud brick vaults and domes

KEYWORDS:

Special properties

Building system without centering or shuttering

Economical aspects

Low cost

Stability

Good

Skills required

Special training

Equipment required

Masonry equipment

Resistance to earthquake

Low

Resistance to hurricane

Very good

Resistance to rain

Depends on external finish

Resistance to insects

Medium to good

Climatic suitability

Hot dry climates

Stage of experience

Traditional in countries like Egypt and Iran

SHORT DESCRIPTION:

· While vaults and domes are self-supporting structural forms when completed, they normally need support and centering while under construction. This usually involves first building an identical vault in wood over which the masonry vault rests, until complete and dried.

· In countries where timber is scarce, this type of vaulting is hardly advantageous. A system of building vaults and domes, without this framework, or shuttering, evolved in countries like Egypt and Iran.

· The drawings overleaf show the sequence of construction of a small house, which the founder members of Development Workshop and some friends built in New Gourna, Upper Egypt, in 1973. They worked as apprentices alongside two Nubian master masons, skilled in the techniques being used.

· The house was built with mud bricks and served, amongst other objectives, as a practical opportunity to master and evaluate the Nubian techniques of building without the use of shuttering, and to obtain a clear guide regarding the relationship of roof span to wall thickness and height for mud brick walls.

· The house stands amongst the buildings designed by Hassan Fathy, who revived this building technique in the 1940s (Bibl. 02.14).

Building Sequence of Experimental House in New Gourna, Upper Egypt (Illustrations by Development Workshop, Bibl. 24.03)


Walls built up to the level of the spring points of the vaults. End wall built up for vault to lean on. Inverted catenary form traced on end wall; Vault is completed; each course of bricks is less inclined, until vault is flush with side walls. Window openings built up with dry bricks - no mortar; Vault building with courses leaning towards end wall so that no formwork or shuttering is required; Walls built up. Arches built over dry brick in windows.


Small vault built in same way as large ones. Loose bricks removed from window openings; Pendentives completed, forming continuous course from which dome can be completed; Circular arches built over vaults to form a base for the dome; Brick courses of dome incline increasingly until dome is finished.

· Further information: Development Workshop (coordinating office in Canada), Box 133, 238 Davenport Road, Toronto, Ontario M5R IJ6, Canada, or (Europe office in France) B.P. 10 Montayral, 47500 Fumel, France.

New Developments

Arches constructed with old car tyres
(Bibl. 24.12)

Simple arches can be constructed over openings by using old car tyres as formwork. This was fried out on a project in India (1986) and found extremely easy to carry out. The sides of the opening, which has the width of the tyre, are erected up to the level at which the arch begins. The tyre is placed on a dry stack of bricks, such that the axis is in line with the top brick layer. The bricks should be laid alternately on each side of the tyre, since excessive load on one side can deform the tyre and distort the shape of the arch. Care must be taken that the lower edges of the bricks touch each other without leaving any gaps. Since the tyre is flexible, it can be removed with ease.


FIGURE

Catenary shaped dome

A catenary shaped template, which rotates around a vertical axis at the centre of the dome, is used to place the bricks with great accuracy to form a curvature which permits only compressive forces to act within the structure. This gives a more stable dome construction than hemispherically shaped domes.

This innovative construction method was developed and tested in 1987 at the Research Laboratory for Experimental Construction, Kassel College of Technology, Federal Republic of Germany, headed by Prof. Gernot Minke.

Earthquake resistant mud/bamboo structures

KEYWORDS:

Special properties

Self-help construction with local materials

Economical aspects

Low cost

Stability

Very good

Skills required

Semi-skilled labour

Equipment required

Traditional local building equipment

Resistance to earthquake

Very good

Resistance to hurricane

Low to medium

Resistance to rain

Low to medium

Resistance to insects

Low

Climatic suitability

All except extremely wet climates

Stage of experience

Experimental

SHORT DESCRIPTION:

· This building system was developed and implemented by John Norton, Development Workshop, France, in a USAID technical assistance project in the Koumbia region of North West Guinea, following the December 1983 earthquake.

· Traditional houses were generally made of wattle and daub walls, and thatch roofs. Similar materials, techniques and house forms had to be used in reconstruction, in order to be sure of acceptance by the people. But the new houses had to be earthquake resistant.

· The solution arrived at was to construct the walls with sun-dried mud bricks and to strengthen them by tying bamboo frames on either side. This external reinforcement can be easily checked for termite or other damage and replaced if necessary, thus avoiding the problem faced by traditional houses, in which the concealed bamboo lattice was usually destroyed and consequently failed during the earthquake.

· With this construction, it was possible to retain the traditional house form and thatch roofing, so that no problems of social acceptance arose.

Further information: John Norton, Development Workshop, B.P. 10 Montayral, 47500 Fumel, France; Bibl. 24.13, 24.14, 25.10.


Plan and Section through Traditional Round House, Koumbia Area; Earthquake Resistant Mud Brick Wall with Bamboo Framework "Sandwiching" (Bibl. 24.13, 24.14); Bamboo tightened by pulling on short sticks attached to wire ends

Adobe brick house

KEYWORDS:

Special properties

Improved traditional building system

Economical aspects

Low to medium costs

Stability

Good

Skills required

Traditional construction skills

Equipment required

Formwork for bricks and concrete, building equipment

Resistance to earthquake

Good

Resistance to hurricane

Good

Resistance to rain

Depends on soil stabilization

Resistance to insects

Medium to good

Climatic suitability

All except extremely hot dry climates

Stage of experience

Increasing applications

SHORT DESCRIPTION:

· This building system was implemented in a housing development project in El Salvador, Central America, initiated by GATE and conducted by the Institute for Tropical Building, Starnberg, Federal Republic of Germany, headed by Dr.Ing. Georg Lippsmeier.

· The aim was to improve the earthquake resistance of traditional adobe brick houses, by self-help methods and with little additional costs.

· The improvements were: strengthening of the site-produced mud bricks by adding lime; providing reinforced concrete foundations and ring beams; rigid connection between roof and supporting walls.

Further information: GATE, Postfach 5180, 6236 Eschborn, Federal Republic of Germany; Bibl. 00.18, 24.01.


Construction Details of Wall, Ring Beam and Roof (Bibl. 24.01)

Modular framed earth block construction

KEYWORDS:

Special properties

Earthquake resistant, light frame, easy assembly

Economical aspects

Low cost

Stability

Good

Skills required

Average construction skills

Equipment required

Soil block press, simple construction equipment

Resistance to earthquake

Good

Resistance to hurricane

Good

Resistance to rain

Depends on soil stabilization

Resistance to insects

Medium to good

Climatic suitability

All except extremely hot dry climates

Stage of experience

Applications in relief projects in Africa

SHORT DESCRIPTION:

· The key elements of this building system are hollow steel connectors and specially formed earth blocks made in a manual block press (with a system of inserts).

· The steel connectors have either square or circular cross-sections and are used to connect straight pipes of square or circular section, or even sawn timber or bamboo components, to form the basic framework, which carries a light, corrugated aluminium sheet roof.

· The earth blocks, produced on the MARO Block Press (see ANNEX), are made to interlock with the framework to form durable walls. This system is ideally suited for disaster relief housing projects. A single truck-load of connectors, roofing sheets and a few block presses can be sufficient to build a group of houses with local soil and bamboo.

· The framework should rest on concrete strip foundations, though for temporary structures no foundation is needed.

· The walls can initially be plastic sheets (for immediate shelter), which are gradually replaced by earth blocks or even locally available burnt clay bricks, such that the quickly erected refugee tent camps are efficiently converted into permanent housing by self-help and low-cost methods. Extensions are possible in all directions.

Further information: Mark Klein, MARO Enterprise, 95 bis Route de Suisse, CH-1290 Versoix (Geneva), Switzerland.

MARO Construction System


Steel connectors with square and circular sections

Lok Bild system

KEYWORDS:

Special properties

Interlocking blocks, high strenght, easy assembly

Economical aspects

Medium to high costs

Stability

Very good

Skills required

Average construction skills

Equipment required

Special framework, standard building equipment

Resistance to earthquake

Very good

Resistance to hurricane

Very good

Resistance to rain

Very good

Resistance to insects

Very good

Climatic suitability

All climates

Stage of experience

Increasing applications; widely tested system

SHORT DESCRIPTION:

· The LOK BILD System was developed by Dr. A. Bruce Etherington of AIT Bangkok and University of Hawaii, and has been tested in Malaysia, Thailand and the Philippines using cement concrete, and in the United Arab Emirates using sulphur concrete.

· The hollow blocks are designed to be assembled without mortar, producing perfectly aligned walls without special masonry skills. The system also includes precast concrete joists, which interlock with the concrete block walls to support in situ floors and roofs, and channel blocks, which are placed on top of the walls to make reinforced concrete ring beams.

· The interlocking blocks have narrow vertical recesses and a central cavity, which when assembled form continuous, vertically aligned holes over the full height of the wall. When cement grout is poured into them, the blocks become permanently locked together. Wherever necessary, eg at corners, cross-walls, or around openings, the large hollow cores can be filled with reinforcement and concrete, providing earthquake resistance.

Further information: Dr. A. Bruce Etherington, Human Settlements Division, Asian Institute of Technology, P.O. Box 2754, Bangkok 10501, Thailand; Bibl. 24.05.


Ordinary block; Half block; Channel block; LOK BLOK Assembly (Bibl. 24.05)


Floor Assembly


House Isometric

Concrete panel house

KEYWORDS:

Special properties

Prefabrication system, quick assembly

Economical aspects

Medium to high costs

Stability

Very good

Skills required

Average construction skills

Equipment required

Formwork for concrete, standard building equipment

Resistance to earthquake

Very good

Resistance to hurricane

Very good

Resistance to rain

Very good

Resistance to insects

Very good

Climatic suitability

All except very hot dry climates

Stage of experience

Experimental

SHORT DESCRIPTION:

· This building system was implemented in housing development projects in Nicaragua and Colombia, initiated by GATE and conducted by ARCO Grasser and Partner, Munich, Federal Republic of Germany.

· The prime requirements were earthquake resistance, simple prefabrication and rapid construction, which resulted in a system of reinforced concrete panels held by vertically fixed U-profiled steel frames, and a timber roof structure with corrugated galvanized iron sheets.

· The precast panels are connected by V-shaped tongue and groove joints, sealed with cement grout after assembly. The ring beam at the top can be of sawn timber or in situ concrete. Wooden door and window frames are made to the same width as the panels and inserted likewise between the steel frames.

· The panels can alternatively be made of wooden or bamboo boards, pumice concrete, ferrocement, or other locally available material.

Further information: GATE, Posffach 5180, 6236 Eschborn, Federal Republic of Germany; Bibl. 24.02.


Construction Details of Wall, Ring Beam and Roof (Bibl. 24.02)

Ferrocement housing units

KEYWORDS:

Special properties

Thin but very rigid wall construction

Economical aspects

Low to medium

Stability

Good

Skills required

Average construction skills

Equipment required

Simple construction tools

Resistance to earthquake

Good

Resistance to hurricane

Good

Resistance to rain

Good

Resistance to insects

Good

Climatic suitability

Warm humid climates

Stage of experience

Experimental

SHORT DESCRIPTION:

· A simple ferrocement house was constructed in 1977 on the Caribbean island of Dominica by Richard Holloway.

· Readily available round-wood poles were used for the load-bearing framework. Chicken-wire was stretched between the poles and plastered with cement mortar, first a rough layer, then a smooth finish. The timber frame remained exposed.

· Care was taken to protect the timber from rainwater and termite attack, by mounting the vertical members on galvanized pipe supports, embedded in exposed concrete footings.

· The roof was made of galvanized iron sheets with a gap left at the top of the wall plate for ventilation. The floors, doors and windows were made of reject quality wood and old boxes, which after painting showed no great difference from new wood.

Further information: Bibl. 24.09.

Construction Details (Bibl. 24.09)


Details of footing

Fibracreto building system

KEYWORDS:

Special properties

Comfortable housing

Economical aspects

Medium to high costs

Stability

Good

Skills required

Masonry skills

Equipment required

Masonry equipment

Resistance to earthquake

Good

Resistance to hurricane

Good

Resistance to rain

Good

Resistance to insects

Good

Climatic suitability

All climates

Stage of experience

Widely used

SHORT DESCRIPTION:

· This building system, patented in Peru under the name FIBRACRETO, basically consists of wood-wool cement panels structured with reinforced concrete columns and beams (Bibl. 24.15).

· It is used for one and two storey houses and is said to reduce construction costs by 35 to 40 % compared to conventional constructions.

· The foundations are 10 cm thick platforms, strengthened below and above the platforms along the axes of the walls.

· The 7.5 cm thick wood-wool cement boards (50 x 200 cm) are assembled with horizontal mortar joints and held together by wooden formwork. When the walls are assembled, the formwork is filled with concrete to produce strong columns, spaced 200 cm apart.

· The roof is made of the same (or thicker) wood-wool cement boards supported by cast-in-situ reinforced concrete beams, and can be flat or sloping.

· The walls and roof are plastered with cement mortar.

Further information: L.R. & T. Arquitectura y Construccion S.A., Arq. Manuel I. de Rivero D'Angelo, Shell # 319 - 702 Miraflores, Lima, Peru.

Bamboocrete construction

KEYWORDS:

Special properties

Cheaper than other equally strong structures

Economical aspects

Low to medium costs

Stability

Good

Skills required

Bamboo and masonry construction skills

Equipment required

Carpentry and masonry tools

Resistance to earthquake

Good

Resistance to hurricane

Good

Resistance to rain

Good

Resistance to insects

Low

Climatic suitability

All except very hot dry climates

Stage of experience

Experimental

SHORT DESCRIPTION:

· The bamboocrete house shown overleaf was implemented in 1976 by Dr. U.C. Kalita, et al (Bibl. 24. 11), Regional Research Laboratory, Jorhat (Assam), India.

· On a concrete foundation with burnt brick base course and flooring, a framework of secondary species timber provides the structural support for infill panels and curved roofing elements made of split bamboo lattice-work, plastered with cement mortar.

· The use of bamboo to substitute steel reinforcement in concrete is of considerable economic interest, as steel is expensive and often imported. However, bamboo shrinks on drying - over 4 times more than the concrete - so that there is no bond between the bamboo and concrete. Furthermore, the alkalinity of concrete gradually destroys the bamboo fibre, which finally loses all its strength.

· Recent research (Bibl.24.10) has shown some possible remedies: 1.Coating the bamboo with hot bitumen and improving bonding by covering it with coarse sand, driving in 25 mm nails or tying coconut fibre ropes around the bamboo (developed by D. Krishnamurthy); 2. Using only the outer section of bamboo (because of its higher tensile strength and elasticity) and twisting bundles of three split-bamboo strips around each other (developed by 0. Hidalgo Lopez).

· Further research is necessary, especially with a view to fibre deterioration.

Bamboo houses

KEYWORDS:

Special properties

High strenght, flexibility, numerous designs possible

Economical aspects

Low to medium costs

Stability

Good

Skills required

Traditional bamboo craftmanship

Equipment required

Tools for cutting, splitting, tying bamboo

Resistance to earthquake

Very good

Resistance to hurricane

Good

Resistance to rain

Depends on protective measures

Resistance to insects

Low

Climatic suitability

Warm humid climates

Stage of experience

Traditional

SHORT DESCRIPTION:

· The examples of bamboo houses shown on the following pages are taken from the excellently illustrated bamboo construction manual by Oscar Hidalgo Lopez (Bibl. 24.07).

· All the structural components and most of the non-structural parts (floors and wall cladding) are made of bamboo. Only very little timber is used and the roof covering can be of any suitable, locally available material (eg thatch, fibre concrete, ferrocement, metal sheeting, cement mortar, or even stabilized, water-resistant soil mortar).

· The bamboo components are joined either by means of lashing materials, dowels, bolts or nails. A great number of possible bamboo connections is shown in the construction manual.

· On account of its low resistance to biological attack and fire, protective measures are necessary (see section on Bamboo).

Further information: Oscar Hidalgo Lopez, Universidad Nacional de Colombia, Apartado Aereo 54118, Bogota, Colombia.


Construction of a Coffee Plant (also suitable for dwelling) (Bibl. 24.07)


Positioning of the supports and erecting the structural framework


Fixing the rafters and construction of upper and lower floors (upper floor and wall cladding with split-bamboo or wooden laths, lower floor covered with stabilized rammed earth).


Bracing of roof structure and completion of roof covering (first with split-bamboo or wooden laths, fixed with nails and wire, then covered with cement mortar, stabilized waterproof mud mortar or thatch).


Bamboo Structure with Prefabricated Space Frame Roof (Wooden boards serve as template and temporary bracing during prefabrication; the walls of the house are not necessarily made of bamboo).


Bamboo House on Stilts


Round House with Thatched Conical Roof (Structural stability is obtained by a bamboo tension ring along the top of the bamboo columns).

Prefabricated timber hut

KEYWORDS:

Special properties

Folding structure, quick assembly, easy transports

Economical aspects

Medium to high costs (depends on timber)

Stability

Good

Skills required

Carpentry skills

Equipment required

Carpentry tools

Resistance to earthquake

Very good

Resistance to hurricane

Good

Resistance to rain

Depends on cladding

Resistance to insects

Low

Climatic suitability

All climates

Stage of experience

Prove design, numerous applications

SHORT DESCRIPTION:

· Based on a German emergency housing design (Prof. Kleinlogel, 1952), a prefabricated timber hut was developed at the Central Building Research Institute, Roorkee, India.

· The aim was to construct a prefabricated house, which can be easily dismantled, transported and re-erected at different sites, particularly for disaster housing.

· The hut is designed to withstand wind velocities up to 130 km/in and a snow load of 100 kg/m2.

· The main structural component is a collapsible timber frame, which defines the cross-section of the house. The length of the building is determined by the number of frames, which are erected 2.44 m apart.

· The standard hut has gci sheets for cladding and roof covering, and plywood boards for interior lining and suspended ceiling. However, any other locally available materials can be used. In cold climates, the cavity between the external cladding and interior lining can be filled with insulating material.

· All that is required is a level piece of ground. The frames can be spiked into the ground or erected on a prepared concrete foundation, if a more permanent structure is required.

Further information: CBRI, Roorkee 247 667, India; Bibl. 24.04.


Prefabricated Timber Hut (Bibl. 24.04)

Prefabricated wooden house

KEYWORDS:

Special properties

Suitable for self-help projects

Economical aspects

Medium costs

Stability

Good

Skills required

Carpentry skills

Equipment required

Carpentry tools

Resistance to earthquake

Good

Resistance to hurricane

Low to medium

Resistance to rain

Low to medium

Resistance to insects

Low

Climatic suitability

Warm humid climates

Stage of experience

Standard construction

SHORT DESCRIPTION:

· The step-by-step construction of this house is shown in an excellently illustrated instruction manual published by UNIDO, which was prepared by the Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, Brazil, for a self-help community building project at Coroados, Manaus, under a contract with the Housing Society for the Amazon State (SHAM).

· Impressions of the contents of this manual are given in Examples of Floors and Walls. The instructions are straightforward and easy to follow.

· An experimental group of 40 houses was built in 1981 - 82, demonstrating the feasibility of the design.

· The fact that the entire house (with the exception of the roof covering) is made of wood calls for very careful consideration of protective measures against biological agents and fire (see section on PROTECTIVE MEASURES).

Further information: Instituto de Pesquisas Tecnologicas (IPT) do Estado de Sao Paulo, S.A., P.O. Box 7141, 05508 Sao Paulo, Brazil; Bibl. 14.22.


Prefabricated Wooden House (Bibl. 14.22)

Timber houses for flood areas

KEYWORDS:

Special properties

Elevated houses and floating structures

Economical aspects

Low to medium costs

Stability

Good

Skills required

Carpentry skills

Equipment required

Carpentry tools

Resistance to earthquake

Good

Resistance to hurricane

Depends on timber connections

Resistance to rain

Good

Resistance to insects

Low

Climatic suitability

Warm humid regions

Stage of experience

Experimental

SHORT DESCRIPTION:

· The great floods of 1982 and 1983, which affected the entire Parana - La Plata region of Paraguay, led to the development of prototype houses, designed to provide safe shelter, even if the floods submerged single storey houses, as they did in 1983.

· The design was jointly developed in 1983 by students of the Catholic University, Asuncion, and flood victims, under the guidance of Prof. Thomas Gieth, Centre for Appropriate Technology, Asuncion, and Dr. Wolfgang Willkomm, University of Hanover, Federal Republic of Germany (Bibl. 24.06, 24.17).

· The design criteria were: protection and escape from floods, low building costs, use of local materials and techniques, suitability for self-help construction.

· The solution was a two-storeyed house with an external stairway and platform around the upper floor. During floods the dwellers can take refuge on top, and planks can be laid between neighbouring houses to serve as bridges, where boats are not available. Local caranday palm logs were used for the framework, wall cladding, windows, doors, and even roof (made by alternately laying hollowed out halved logs, like Spanish tiles).

· To overcome the foundation problems associated with this design, an alternative solution was worked out in 1984 by Behrend Hillrichs, architectural student at the University of Hanover (Bibl. 24.08), suggesting houses that can float on the flood waters.


Construction System of Houses for Flood Areas CTA, Paraguay; Grouped houses with escape platforms


Principles of Floating Houses for Flood Areas (Bibl. 24.08)

Normal position of houses on dry ground

Position of houses during flood: the poles keep them in a stable position.

View of houses from above: short bridges connect the platforms.

Normal raft-type platform

Advantages: simple construction; stable position during floods.

Problems: gradual wetting of floor; sinking of raft with increasing load of people and belongings and with gradual water absorption; risk of pole buckling under lateral water pressure.

Platform on floats (eg empty oil barrels)

Advantages: platform raised above water level; high load-bearing capacity; no gradual sinking.

Problems: more complicated construction maintenance of good condition of floats (no holes!); instability during floods (tendency to "dance" on the waves).

Rha-lime prototype house

KEYWORDS:

Special properties

Substantial replacement of cement

Economical aspects

Medium costs

Stability

Very good

Skills required

Standard construction skills

Equipment required

Conventional building equipment

Resistance to earthquake

Very good

Resistance to hurricane

Very good

Resistance to rain

Very good

Resistance to insects

Very good

Climatic suitability

All climates

Stage of experience

Experimental

SHORT DESCRIPTION:

· The first house to be built, using to a large extent rice husk ash (RHA) and lime as substitute for cement, stands on the premises of the National Building Research Institute, Karachi, Pakistan (also see Pozzolanas).

· Portland cement was used to stabilize the soil for the foundation (3 % cement); for compressed soil blocks (5 % cement) used to construct the plinth; for the floor; and for concrete door and window frames.

· Structural components such as the roof, beams, lintels, projection slabs (sunshade), overhead water tank, were also made with portland cement, but with 30 % of the required amount replaced by RHA and lime.

· The hollow blocks and mortar used for the load-bearing walls were made only with RHA and lime as binder, just as the external plaster.

· The appearance, structural performance and durability of the house is no different from conventional constructions, using portland cement as the only binder, but it saved 37 % of the costs and showed a way to solve a waste disposal problem.

Further information: National Building Research Institute, F-40, S.I.T.E., Hub River Road, Karachi, Pakistan; Bibl. 24.16.


RHA-Lime Prototype House at NBRI, Karachi (Bibl. 24.16)

TO PREVIOUS SECTION OF BOOK TO NEXT SECTION OF BOOK