2521-2281 2521-2281 S2521-22812020000300086 10.52379/mcs.v4i3.158 Paraguay 00 12 2020 00 12 2020 4 3 86 87 1 2020 19 6 6 3451-3 2 2020 4 3 3 2473974X20948835 3 2020 36 4 4 4 2020 1-3 5 2020 173 4 4 317-20 6 2020 22 2 2 20l02627 7 2020 66 4 4 317-20