6
by Siebel, Karl
Published 1922
Vieweg+Teubner Verlag

8
by Gödderz, Johann
Published 1949
VS Verlag für Sozialwissenschaften

12
by Henning, Friedrich
Published 1915
Vieweg+Teubner Verlag

14
by Bertelsmann, Lene
Published 1939
Vieweg+Teubner Verlag

16
by Melville, Harry W.
Published 1958
VS Verlag für Sozialwissenschaften

18
by Caskel, Werner
Published 1953
VS Verlag für Sozialwissenschaften

19
by Hahn, Otto
Published 1953
VS Verlag für Sozialwissenschaften

20
by Quick, August Wilhelm
Published 1964
VS Verlag für Sozialwissenschaften