Não informado. (1977). IABSE Surveys. International Association for Bridge and Structural Engineering.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. IABSE Surveys. Zurich, Suíça: International Association for Bridge and Structural Engineering, 1977.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. IABSE Surveys. International Association for Bridge and Structural Engineering, 1977.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.