2521-2281 2521-2281 S2521-22812021000200115 10.52379/mcs.v5i2.178 Venezuela Paraguay Venezuela 00 08 2021 00 08 2021 5 2 115 116 1 2009 60 124-34 2 2001 60 5-20 3 2012 55 2085-8 4 2010 41 1 1 14-24 5 2019 48 3 3 140-8