Não informado. Studies in Geography. Northwestern University, Department of Geography.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Studies in Geography. Evanston, Ill: Northwestern University, Department of Geography.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Studies in Geography. Northwestern University, Department of Geography.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.