1390-6542 1390-6542 S1390-65422018000100025 10.29019/enfoqueute.v9n1.242 Ecuador Spain 00 03 2018 00 03 2018 9 1 25 33

2014 2014 Paris, France 2009 2014 2014 2007 52 449 449 2004 13 4 4 343-70 1992 1-12 1988 14 6 6 758-73 2017 Quito, Ecuador 2016 2016 Linz, Austria 2017 321-32 2015 2015 336-41 2011 2004 3 1 1 6-16 2013 2001 2017 Indianápolis, USA 2013 2013 2017 2013 2013 2014 2017