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.
Παραπομπή σε μορφή Chicago (17η εκδ.)Okpon, Stephen Nelson, και E. A. Aduayi. Nitrogen Nutrition of White Yam (Dioscorea Rotundata Poir) Grown in Two Selected Locations of Southwestern Nigeria. Obafemi Awolowo University, 2014.
Παραπομπή σε μορφή MLA (9th εκδ.)Okpon, Stephen Nelson, και 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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