December 2006. Retrieved 2008-04-08. ↑ Achterberg, E. (1999), "Impact of Los Frailes mine spill on riverine, estuarine and coastal waters in southern Spain", Water Res., 33: 3387, doi:10.1016/S0043-1354(99)00282-1 . ↑ Amerithrax or Anthrax Investigation, U.S. Federal Bureau of Investigation. ↑ Smith, R. D. (2006).