2602-8484 2602-8484 S2602-84842016000200013 10.29166/revfig.v1i2.862 Ecuador Ecuador 00 12 2016 00 12 2016 2 2 13 16

2010 47 47 823-8 1989 2005 38 4 4 329-43 ISRM 1985 22 51-60 1993 33 209-25 2004 104 215-22 1986 33 3-12 1995 151-5 2011 118 82-92