Published by arrangement with the
Institut africain pour la d�veloppement �conomique et social
B.P. 8008, Abidjan, C�te d'Ivoire
FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
Rome 1977
FAO Economic and Social Development Series No. 3/12
Reprinted 1982, 1983, 1990
P-69
ISBN 92-5-100152-9
© French edition, Institut africain pour le d�veloppement �conomique et social (INADES) 1971
© English edition, FAO 1977