Werner-Spanhoofd, A. Lehrbuch der deutschen sprache: A practical course in German for high school academy of college / by Arnold Werner-Spanhoofd.
Παραπομπή σε μορφή Chicago (17η εκδ.)Werner-Spanhoofd, Arnold. Lehrbuch Der Deutschen Sprache: A Practical Course in German for High School Academy of College / by Arnold Werner-Spanhoofd. London : D. C. Heath & Co., 1921.
Παραπομπή σε μορφή MLA (8th εκδ.)Werner-Spanhoofd, Arnold. Lehrbuch Der Deutschen Sprache: A Practical Course in German for High School Academy of College / by Arnold Werner-Spanhoofd.
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