1870-199X 1870-199X S1870-199X2008000400168 10.22201/fo.1870199xp.2008.12.4.15623 Mexico Mexico Mexico Mexico 00 00 2008 00 00 2008 12 4 168 172

1 1934 3 1-4 2 1959 3 1971 4 1983 106 75-7 5 1958 29 210-2 6 1966 609-20 7 1991 46 247-64 8 1992 6 302-55 9 1987 115 565-71 10 1995 5 475-9 11 1993 12