Lavelle, P.; Dugdale, R.; Scholes, R.; Berhe, A. A.; Carpenter, E.; Codispoti, L. (2005). "12. Nutrient cycling"(PDF). Millennium Ecosystem Assessment: Objectives, Focus, and Approach. Island Press. ISBN978-1-55963-228-7. Archived from the original(PDF) on 2007-09-28. Retrieved 2022-09-25.
Lavelle, P.; Dugdale, R.; Scholes, R.; Berhe, A. A.; Carpenter, E.; Codispoti, L. (2005). "12. Nutrient cycling"(PDF). Millennium Ecosystem Assessment: Objectives, Focus, and Approach. Island Press. ISBN978-1-55963-228-7. Archived from the original(PDF) on 2007-09-28. Retrieved 2022-09-25.