2477-9199 2477-9199 S2477-91992016000200062 10.26807/cav.v0i01.20 Ecuador Ecuador 00 06 2016 00 06 2016 1 62 69

2006 2010 4 45-65 2003 2011 45-58 2006 2011 59-65 2013 2008 47-64 2008 2008 2010 CAV FADA PUCE 2016 1997 2012