0366-5232 0366-5232 S0366-52322020000200330 10.15446/caldasia.v42n2.73059 Mexico Mexico 00 12 2020 00 12 2020 42 2 330 332

2007 1995 76 7 7 2084-96 1999 22 6 6 659-82 2010 35 2 2 165-75 Statsoft Inc 1995 2004 162 2 2 413-26 2006 20 5 5 778-89