1. Growth of legumes at different levels of liming;Barnard;Trop. Agric. (Trinidad),1988
2. Identification and control of trace element deficiencies. V. Iron deficiency;Beyers;Decid. Fruit Grower,1971
3. Identification and control of trace element deficiencies. I. Zinc deficiency;Beyers;Decid. Fruit Grower,1971
4. Principles of plant physiology;Bonner,1952
5. Zinc;Chapman,1966