Journal of the Pennsylvania Academy of Science. Penn State University Press.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रJournal of the Pennsylvania Academy of Science. Penn State University Press.
एमएलए (9वां संस्करण) प्रशस्ति पत्रJournal of the Pennsylvania Academy of Science. Penn State University Press.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.