Simón Pedro Izcara Palacios (2003), Agricultura y Medio Ambiente en la Unión Europea: la contaminación por nitratos, UAT, México, 284 p.

Works are released under a Creative Commons License (Creative Commons 4.0. Atribución-NoComercial-CompartirIgual) which provides unrestricted use, copy and redistribution in any medium or format and remix, transform and build upon the original work properly cited. The Creative Commons License stipulates that: "You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work)."