1405-3195 1405-3195 S1405-31952007000400479 Mexico Mexico Mexico 00 06 2007 00 06 2007 41 4 479 489

2002 8 263-71 2000 44 1-9 1985 180 75-80 1995 146 64-70 1986 116 11-7 2000 1367 1982 303-12 1989 35 97-112 1989 34 203-13 1991 28 166-234 1978 43 1828-31 1997 47 363-71 1986 433 1996 14 143-7 1987 25 2001 35 451-8 2005 1988 23 393-9 1988 23 103-14 1997 150 674-8 1995 46 95-107 1995 47 13-27 1962 52 746 1985 113 30-5 1991 1 399-426 1996 480 2001 3 2001 5 1994 29 23-9 1994 238 1999 107 142-9 1995 46 491-507