1390-6542
1390-6542
S1390-65422017000500053
10.29019/enfoqueute.v8n5.180
Ecuador
00
12
2017
00
12
2017
8
5
53
66
[
2007
]
[
2005
223-34
]
[
2012
]
[
2010
]
[
2009
]
[
2005
243-64
]
[
2001
]
[
2010
]
[
2010
]
[
2000
11
3
3
223-31
]
[
2010
]
[
2005
]
[
2010
]
[
2000
]
[
2008
]
[
2006
]
[
2006
17
1
1
35-43
]
[
1988
39
2
2
162-8
]
[
2005
]
[
(200
6
]
[
2011
]
[
1997
]
[
2007
]