References
1. Kenneth K.GKintu, AmoloOmoding ,Richard .S.Kikomeko, 2007. MK secondary agriculturestudent’s Book one, page 135-168
2. Bernard P.K.YerimaandE.VanRanst, 2005. Introduction to Soil Science:soils of tropics.page 300-305
3. B.Nkhwa, E. Dlamini, G.Mcleod, J.Kasozi, M.Letaba,T.T. Moonyane, S. Magagula, 2009. Macmillan Agriculture for Southern Africa,Page 56-62 and 117-118.
4. Anthony young, 2010. Tropical soils and soil survey. Page 285-302
5. Farmer’s Diary ,2008-2009.