APA (7th ed.) Citation

Qiao, J., Qiao, Y., & Qiao, S. (1990). Six-digit coding method. Communications of the ACM, 33, 491. https://doi.org/10.1145/78607.78609

Chicago Style (17th ed.) Citation

Qiao, Jinan, Yizheng Qiao, and Sanzheng Qiao. "Six-digit Coding Method." Communications of the ACM 33 (1990): 491. https://doi.org/10.1145/78607.78609.

MLA (9th ed.) Citation

Qiao, Jinan, et al. "Six-digit Coding Method." Communications of the ACM, vol. 33, 1990, p. 491, https://doi.org/10.1145/78607.78609.