1992-8238 1992-8238 S1992-82382021000200061 El Salvador 00 12 2021 00 12 2021 73 61 73

2017 tercera ed. 2010 145 1999 2011 2014 3era. ed 1985 2017 27-40 2009 MINED 2010 1983 1996 2012 28-36 PNUD 2016 2011 2007 2010 1978