Schefold, B. (2003). Robert E. Norton: Secret Germany. Stefan George and his circle: Eine Widerlegung / Bertram Schefold. Castrum Peregrini.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रSchefold, Bertram. "Robert E. Norton: Secret Germany. Stefan George and His Circle: Eine Widerlegung / Bertram Schefold." Castrum Peregrini 2003.
एमएलए (8वां संस्करण) प्रशस्ति पत्रSchefold, Bertram. "Robert E. Norton: Secret Germany. Stefan George and His Circle: Eine Widerlegung / Bertram Schefold." Castrum Peregrini, 2003.
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