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Shelton, A.M.; Badenes-Perez, F.R. (6 December 2005). "Concepts and applications of trap cropping in pest management". Annual Review of Entomology. 51 (1): 285–308. doi:10.1146/annurev.ento.51.110104.150959. PMID16332213.
Wagner, S. C. (2011). "Biological Nitrogen Fixation". Nature Education Knowledge. 3 (10): 15. Archived from the original on 13 September 2018. Retrieved 1 May 2019.