1. Alexander M. 1965a. Denitrifying bacteria.In: Black CA, Evans DD, Ensminger LE, White JL, Clark FE (eds), Methods of soil analysis Part 2 chemical and microbiological properties. Wisconsin: American Society of Agronomy, Inc., pp. 1484–1486.
2. Alexander M. 1965b. Most-probable-number method for microbial population. In: Black CA, Evans DD, Ensminger LE, White JL, Clark FE (eds), Methods of soil analysis Part 2 chemical and microbiological properties. Wisconsin: American Society of Agronomy, Inc., pp. 1467–1472.
3. Alexander M, Clark FE. 1965. Nitrifying bacteria. In: Black CA, Evans DD, Ensminger LE, White JL, Clark FE (eds), Methods of soil analysis Part 2 chemical and microbiological properties. Wisconsin: American Society of Agronomy, Inc., pp. 1477–1483.
4. Arocena JM, Opio C. 2003. Prescribed re-induced changes in properties of sub-boreal forest soils. Geoderma, 113: 1–16
5. Ball DF. 1964. Loss on ignition as an estimate organic matter and organic carbon in non-calcareous soil. Journal of Soil Science, 15: 84–92.