APA (7 वां संस्करण) प्रशस्ति पत्र

Das, B. M., & Sobhan, K. (2014). Principles of geotechnical engineering (Eighth edition.). Cengage Learning.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Das, Braja M., और Khaled Sobhan. Principles of Geotechnical Engineering. Eighth edition. Stamford, CT: Cengage Learning, 2014.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Das, Braja M., और Khaled Sobhan. Principles of Geotechnical Engineering. Eighth edition. Cengage Learning, 2014.