1. Bettany, J R and Stewart, J WB. Sulphur cycling in soils. Proceedings of the International Sulphur '82 Conference. Edited by: More, A I. Vol. II, pp.767–786. London: The British Sulphur Corporation.
2. Microbial Biomass and Activity in a Laterite Soil Amended with Municipal Solid Waste Compost
3. Chapter 6 Soil Organic Sulfur and Fertility
4. De Kok LJ, Schnug E, editors. 2005. Proceedings of the 1st Sino-German Workshop on Aspects of Sulpfur Nutrition of Plants; 23–27 May 2004, Shenyang, China. Braunschweig: Bundesforschungsanstalt für Landwirtschaft (FAL). 182 p