1
2
3
Published in 2001
Repository
4
5
7
8
Published in 2004
Repository
9
10
11
12
Published in 1992
Repository
13
Published in 2010
Repository
14
15
16
article
Published in 2000
Repository Repositorio SENESCYT
17
Published in 2012
Repository
18
Published in 2000
Repository
19
Published in 1998
Repository
20