0186-7210 0186-7210 S0186-72102013000300735 10.24201/edu.v28i3.1452 Mexico 00 12 2013 00 12 2013 28 3 735 768

1997 1972 1986 1973 1987 361-86 1974 2008 18 36 36 75-86 2011 1984 2003 3 31-53 2004 1986 2010 99 99 60-3