APA (7th ed.) Citation

Chayut, I., Cook, C., & Olczak, A. (1989). X user reference guide (1. ed.). ASP Inc.

Chicago Style (17th ed.) Citation

Chayut, Ira, Camille Cook, and Anatole Olczak. X User Reference Guide. 1. ed. San Jose, CA: ASP Inc, 1989.

MLA (9th ed.) Citation

Chayut, Ira, et al. X User Reference Guide. 1. ed. ASP Inc, 1989.