2448-6442 2448-6442 S2448-64422018000200439 10.24201/es.2018v36n107.1589 Mexico 00 08 2018 00 08 2018 36 107 439 443 2000 1985 1991 1999 1963 2001 1992 31/32 31/32 84-98 1985 1992 31/32 31/32 99-113 1974 I