Heft. Engineering Education and Practice. University of Notre Dame Press.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रHeft. Engineering Education and Practice. University of Notre Dame Press.
एमएलए (9वां संस्करण) प्रशस्ति पत्रHeft. Engineering Education and Practice. University of Notre Dame Press.
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