@ARTICLE {UNAMMA:1989a, title = {Effects of tropical weeds on yield in white yam (Dioscorea rotundata Poir)}, author = {Unamma, R. P. A. and Akobundu, I. }, journal = {Weed Research}, year = {1989}, volume = {29}, number = {1}, pages = {1--6}, issn = {0043-1737}, note = {RTB; Root and Tuber; Yam}, }