APA (7th ed.) Citation

O'Reilly & Associates. (1990). X toolkit intrinsics reference manual (2nd ed. for X11, release 4.). O'Reilly & Associates.

Chicago Style (17th ed.) Citation

O'Reilly & Associates. X Toolkit Intrinsics Reference Manual. 2nd ed. for X11, release 4. [Sebastopol, Calif.]: O'Reilly & Associates, 1990.

MLA (9th ed.) Citation

O'Reilly & Associates. X Toolkit Intrinsics Reference Manual. 2nd ed. for X11, release 4. O'Reilly & Associates, 1990.