1. Allen, O. N. (1953). Experiments in soil bacteriology. Minneapolis, MN: Burges Publishers.
2. Alvarez, R. J., Ortiz, S. R., & Alcaraz, A. F. (2001). Edaphic characterization and soil ionic composition influencing plant zonation in a semiarid Mediterranean salt marsh. Geoderma, 99, 81–98.
3. APHA. (2005). Standard methods for the examination of water and wastewater (20th ed.). Washington DC: American Public Health Association (APHA).
4. Bossio, D., Critchley, W., Geheb, K., Van Lynden, G., & Mati, B. (2007). Conserving soil—protecting water comprehensive assessment of water management in agriculture: Water for food, water for life. Sterling, VA: Stylus Publishing.
5. Casida, L. E., Klein, D. A., & Santoro, T. (1964). Soil dehydrogenase activity. Soil Science, 98, 371–376.