2521-2281 2521-2281 S2521-22812021000100001 10.52379/mcs.v5i1.175 Paraguay 00 04 2021 00 04 2021 5 1 1 2 1 2020 2 2020 67 5 5 674-96 3 2015 62 1 1 51-66 4 2009 56 1 1 97-109 5 2021 5 1 1 3-10