0120-1263 0120-1263 S0120-12632018000200389 10.18566/escr.v26n57.a07 Colombia 00 12 2018 00 12 2018 26 57 389 406

1965 2000 2005 2006 2013 2015 2003 2003 1997 1999 2007 1973 1976 2013 2006 1970 1999 1985 2004 2008 1986