Krapp, K. M. (1998). Notable twentieth-century scientists: Supplement. Gale Research.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रKrapp, Kristine M. Notable Twentieth-century Scientists: Supplement. Detroit: Gale Research, 1998.
एमएलए (9वां संस्करण) प्रशस्ति पत्रKrapp, Kristine M. Notable Twentieth-century Scientists: Supplement. Gale Research, 1998.
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