@INBOOK {NG:1997d, title = {Germplasm conservation in food yams (Dioscorea spp.): constraints, application and future prospects}, author = {Ng, S. Y. C. and Ng, N. Q. }, editor = {Razdan, M. K. and Cocking, E. C. }, year = {1997}, volume = {1}, type = {Conservation of plant genetic resources in vitro}, pages = {257--286}, publisher = {Science Publishers}, address = {Enfield, NH, USA}, note = {RTB; Root and Tuber; Yam}, }