APA (7 वां संस्करण) प्रशस्ति पत्र

Darley, H. C. H., & Gray, G. R. (1988). Composition and properties of drilling and completion fluids (5th edition.). Gulf Pub. Co., Book Division.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Darley, H. C. H., और George Robert Gray. Composition and Properties of Drilling and Completion Fluids. 5th edition. Houston: Gulf Pub. Co., Book Division, 1988.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Darley, H. C. H., और George Robert Gray. Composition and Properties of Drilling and Completion Fluids. 5th edition. Gulf Pub. Co., Book Division, 1988.