B. O. Unagwu and R. U. Ayogu, “Animal manure application effects on soil properties and okra ( Abelmoschus esculentus L) growth and yield performance”, Int. J. Recycl. Org. Waste Agric., vol. 11, no. 3, Jun. 2022, doi: 10.30486/ijrowa.2022.1910512.1137.