Metzke, E., author
Heidelberg Kerle 1949
Buku Referensi
Ziegenfuss, W., author
Berlin de Gruyter 1949
Buku Referensi
Julia, Didier, author
Paris, Librairie Larousse
Buku Referensi
Brugger S.J., Walter, author
Wieh Herder 1948
Buku Referensi
Landmann, Michael
Bouvier Verlag Herbert Grundmann, 1977
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