1
published 2012
Journal
2
published 2005
Journal
3
published 2002
CD-ROM
5
published 1994
CD-ROM
6
published 1992
Journal
7
published 1992
Journal
9
10
published 1991
Journal
11
published 1989
Journal
12
published 1989
Journal
13
published 1989
Journal
14
published 1988
Journal
15
published 1983
Journal
16
published 1969
Journal
17
published 1921
Journal
19
published 2013
Kostenfrei, Verlag
Electronic Journal
20
published 2013
Kostenfrei, Verlag
Electronic Journal