1990-8644 1990-8644 S1990-86442021000400374 Ecuador 00 08 2021 00 08 2021 17 81 374 378

2017 1994 915-44 2021 15 15 17-34 2012 2011 356 109-31 2008 2 39 39 314-9 2015 15 2 2 71-80 2017 2008 47 2 2 2-10 2020 34 3 3