2072-8174 2072-8174 S2072-81742019000200109 10.18004/rdn2019.0011.02.109-113 Paraguay 00 12 2019 00 12 2019 11 2 109 113

1 2010 28 12 12 2114-22 2 2011 29 33 33 4381-6 3 2016 6 3 3 251-5 4 2011 13 5 5 219 5 2004 19 4 4 246-53 6 2008 41 51-4