@INBOOK {NG:1991e, title = {In vitro conservation and distribution of root and tuber crop germplasm}, author = {Ng, S. Y. C. }, year = {1991}, type = {Crop genetic resources of AFrica, Vol. II, edited by N.Q. Ng, P. Perrino, F. Attere, and H. Zedan}, pages = {95--106}, publisher = {International Institute of Tropical Agriculture (IITA); IBPGR; UNEP; CNR}, address = {Italy; Ibadan, Nigeria}, }