APA (7th ed.) Citation

Cay, N. B., Gil, A. J., Guzman, M. K., & Reyes, D. (1973). This challenging world. Alemar-Phoenix.

Chicago Style (17th ed.) Citation

Cay, Nila Barlaan, Avelina Juan Gil, Maybelle Koch Guzman, and Danny Reyes. This Challenging World. Quezon City: Alemar-Phoenix, 1973.

MLA (9th ed.) Citation

Cay, Nila Barlaan, et al. This Challenging World. Alemar-Phoenix, 1973.