1990-8644 1990-8644 S1990-86442020000400231 Cuba Ecuador 00 08 2020 00 08 2020 16 75 231 237

2017 9 4 4 37-43 2019 41 163 163 11-25 2016 12 52 52 2015 7 3 3 155-9 2018 22 2 2 192-213 2015 40 10 10 656-63 2017 10 3 3 55-71