1
by Hirvela
Published 2004
2
by Grabe
Published 2009
3
by BIALYSTOK
Published 1994
4
Published 2001
5
by ELLIS
Published 1994
6
by ELLIS
Published 1997
7
Published 2006
8
Published 2007
9
by Dornyei
Published 2001
10
Published 1994
11
12
by ELLIS
Published 1997
13
by ELLIS
Published 1997
14
by ELLIS
Published 1997
15
by COOK
Published 2001
16
Published 1989
17
by SCOVEL
Published 2001
18
by Nunan
Published 1999
19
by COOK
Published 1996
20
by COHEN
Published 1998