References
- Arnold , G.W. 1964 . “ Factors within plant associations affecting the behaviour and performance of grazing animals ” . In Grazing in terrestrial and marine environments , Oxford : Blackwell Scientific Publications .
- Voisin , A. 1961 . Grass productivity , London : Grosby Lockwood .
- New Address: Computer Section, Department of Agricultural Technical Services, P.B. XI116, P.O. Vallis, Pretoria.