2218-3620 2218-3620 S2218-36202020000100237 Ecuador 00 02 2020 00 02 2020 12 1 237 243

2003 8 2 2 19-24 1995 3 17 17 5-11 2009 8 15 15 105-14 2006 2012 2010 2007 2006 2007 487-510 2004 2013 2013 12 3 3 21-31 2016 4 3 3 303-8