 Bibliografía
 http://www.springerlink.com/journals/?M
  UD=MP
 http://www.bvs.org.ec/php/index.php
 http://search.proquest.com/index
 http://site.ebrary.com/lib/utasp/home.a
  ction
 http://find.galegroup.com/menu/comm
  onmenu.do?userGroupName=uta_cons

Dominio en internet