4
Published 1997
(CARLI) (Other Sources: (UIUdb)4111807)
Book
5
by Ritter, Gerhard Albert.
Published 1973
Book
6
by Ritter, Gerhard Albert.
Published 1992
Book
7
by Ritter, Gerhard Albert.
Published 1980
(CARLI) (Other Sources: (UIUdb)434543)
Book
9
by Ritter, Gerhard Albert.
Published 1995
(CARLI) (Other Sources: (UIUdb)3912101)
Book
10
Published 1983
(CARLI) (Other Sources: (UICdb)584547, (UIUdb)701413)
Book
12
by Ritter, Gerhard Albert.
Published 1983
(CARLI) (Other Sources: (NIUdb)205341, (UIUdb)786288)
Book
13
by Ritter, Gerhard Albert.
Published 1986
Book
14
by Kotowski, Georg,, Kotowski, Georg,
Published 1966
Book
15
by Ritter, Gerhard Albert.
Published 1975
(CARLI) (Other Sources: (SICdb)663487, (UIUdb)221308)
Book
16
by Ritter, Gerhard Albert.
Published 1975
(CARLI) (Other Sources: (ISUdb)542551)
Book
17
Published 1965
Book
18
by Ritter, Gerhard Albert.
Published 1998
Book