2550-6722 2550-6722 S2550-67222019000300120 10.37135/chk.002.09.10 Ecuador Ecuador 00 12 2019 00 12 2019 9 120 133

2014 2018 2015 69 18 2009 7 2015 2006 2010 2017 2016 2017 2012 2009 2007