Helmling, Brigitte
Munchen J. Gotteswinter GmbH 1986
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Frankfurt : am Main Fischer Taschenbuch Verlag GmbH, 1981
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Padang : FBSS UNP Press
Majalah, Jurnal, Buletin
Djogjakarta [t.p.] 1969
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Baumann, Barbara
Munchen Hueber c1985
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