References
- Graven , E.H. 1967 . Some edaphic considerations regarding the introduction of legumes into veld . Proc. Grassld. Soc. Sth. Afr. , 2 : 63 – 70 .
- Griffiths Davies , J. and Shaw , N.H. 1964 . “ The nature of the problem. Ch. 1 and 2 ” . In Some concepts and methods in subtropical research , C.A.B. Bull. 47, Farnham Royal, Bucks Brisbane : Staff C.S.I.R.O .