2218-3620 2218-3620 S2218-36202019000400118 Ecuador 00 12 2019 00 12 2019 11 4 118 123

1999 1994 9 99-111 1998 1997 2005 2010 1990 2003 2001 2002 25 279-305 2005 2007 1996 2006 2002