2550-6587 2550-6587 S2550-65872018000200035 10.33936/rehuso.v3i2.1373 Ecuador Ecuador Ecuador Ecuador 00 07 2018 00 07 2018 3 2 35 43

2013 2013 2009 19 2 2 133-47 2002 2006 2002 2004 2002 2008 2000 2003 2009 19 2 2 109-132. 2011 2010