Okpara, D.A. and Omaliko, C.P.E. (2012) “Productivity of yambean (Sphenostylis stenocarpa) - yellow yam (Dioscorea cayenensis) intercropping”, The Indian Journal of Agricultural Sciences, 65(12). Available at: https://epubs.icar.org.in/index.php/IJAgS/article/view/19165 (Accessed: 24 October 2025).