Clark, Todd D. (2007), "Spain", PharmaHandbook: a guide to the international pharmaceutical industry (Google Books) (5 ed.), New Orleans, Louisiana, United States: Value of Insight Consulting, p. 381, ISBN978-0-9795443-0-9, OCLC254331162, retrieved May 7, 2011
Clark, Todd D. (2007), "Spain", PharmaHandbook: a guide to the international pharmaceutical industry (Google Books) (5 ed.), New Orleans, Louisiana, United States: Value of Insight Consulting, p. 381, ISBN978-0-9795443-0-9, OCLC254331162, retrieved May 7, 2011