0379-3982 0379-3982 S0379-39822017000400150 10.18845/tm.v30i4.3424 Costa Rica Costa Rica Costa Rica Costa Rica Costa Rica Costa Rica 00 12 2017 00 12 2017 30 4 150 156

[1] MAG 2008 [2 ] 2014 [3] 2011 8 73-94 [4] 2010 51 319-24 [5] 2006 3 9-20 [6] 2011 59 2 2 [7] 2010 [8] 2010 [9] 2001 49 11 11 5489-93 [10] 2005 [11] 2012 45 22-31 [12] 2007 139 143-56 [13] 2008 9 231-41