@ARTICLE {HERREN:H.R 1983a, title = {The Africa-wide biological control programme of cassava mealybug and green spider mites: achivements and control strategies}, author = {Herren, H. R. }, journal = {Paper presented at USAID Regional Meeting 7-11 December 1983,Harare, Zimbabwe}, year = {1983a}, pages = {7--11}, note = {RTB; Root and Tuber; Cassava}, }