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Good AG, Shrawat AK, Muench DG (December 2004). "Can less yield more? Is reducing nutrient input into the environment compatible with maintaining crop production?". Trends in Plant Science. 9 (12): 597–605. doi:10.1016/j.tplants.2004.10.008. PMID15564127.
Davidson EA, Belk E, Boone RD (February 1998). "Soil water content and temperature as independent or confounded factors controlling soil respiration in a temperate mixed hardwood forest". Global Change Biology. 4 (2): 217–227. Bibcode:1998GCBio...4..217D. doi:10.1046/j.1365-2486.1998.00128.x. ISSN1354-1013.
Steiner Z, Klarić I, Novoselec J, Klir Ž, Antunović B, Babić I, et al. (2019). "Research on influence of different non-protein nitrogen (NPN) compounds in beef cattle feeding". Journal of Central European Agriculture. 20 (1): 31–35. doi:10.5513/JCEA01/20.1.2378. ISSN1332-9049.