Okpon, S. N., & Aduayi, E. A. (2014). Nitrogen Nutrition of White Yam (Dioscorea rotundata Poir) Grown in Two Selected Locations of Southwestern Nigeria. Obafemi Awolowo University.
Čikaški stil citiranja (17. izdanje)Okpon, Stephen Nelson, i E. A. Aduayi. Nitrogen Nutrition of White Yam (Dioscorea Rotundata Poir) Grown in Two Selected Locations of Southwestern Nigeria. Obafemi Awolowo University, 2014.
MLA način citiranja (9. izdanje)Okpon, Stephen Nelson, i E. A. Aduayi. Nitrogen Nutrition of White Yam (Dioscorea Rotundata Poir) Grown in Two Selected Locations of Southwestern Nigeria. Obafemi Awolowo University, 2014.
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