by Nkang, N M, Edet, E O, Oniah, M O, Okon, X A
Published in Global journal of agricultural sciences (01.01.2011)

by Eze, Christopher C, Lemchi, JI, Ugochukwu, Albert I, Eze, V C, Awulonu, CAO, Okon, A X
Published in IDEAS Working Paper Series from RePEc (01.01.2010)

by Okon, XA, Abang, SO, Akpan, OE, Nkang, NM
Published in UNISWA research journal of agriculture, science and technology (25.08.2006)