0185-1918 0185-1918 S0185-19182008000200013 10.22201/fcpys.2448492xe.2008.203.41992 Mexico 00 08 2008 00 08 2008 50 203 13 52

1977 1990 1992 1997 1986 1993 1979 2004 1983 1970 1994 1997 1988 1987 1977 1999 1986 1986 1991 1971 1993 1981 2-3 2-3 1981 1982 2000 2001 1978 1994 1988 1994 1997 1999 1993 1997 2001 20 20 2005 1976 1982 1995 1983 1995 1994 1994 1984 1997 1994 1994 1969 1983 1992 1994 1994 2002 1979 1979 1994 1975 1998 2004 2006 1983 2003 1994 1987 1999 1982 1999 1976 2006 2007 1975 2000 1 2 2 1949 1979 1975 1959 2006 1966 1995