Smith, V. H.; Tilman, G. D.; Nekola, J. C. (1999). "Eutrophication: Impacts of excess nutrient inputs on freshwater, marine, and terrestrial ecosystems". Environmental Pollution (Barking, Essex : 1987). 100 (1–3): 179–196. doi:10.1016/S0269-7491(99)00091-3. PMID 15093117.
Carpenter, S. R.; Caraco, N. F.; Correll, D. L.; Howarth, R. W.; Sharpley, A. N.; Smith, V. H. (August 1998). "Nonpoint Pollution of Surface Waters with Phosphorus and Nitrogen". Ecological Applications. 8 (3): 559. doi:10.2307/2641247Arhivat în , la Wayback Machine.. hdl:1813/60811. JSTOR 2641247.
Carpenter, S. R.; Caraco, N. F.; Correll, D. L.; Howarth, R. W.; Sharpley, A. N.; Smith, V. H. (August 1998). "Nonpoint Pollution of Surface Waters with Phosphorus and Nitrogen". Ecological Applications. 8 (3): 559. doi:10.2307/2641247Arhivat în , la Wayback Machine.. hdl:1813/60811. JSTOR 2641247.