Cita APA (7th ed.)

Aquino, D. R. C., & Cruz, A. R. (2020). Obligations & contracts (Third edition.). Central Book Supply, Inc.

Cita Chicago (17th ed.)

Aquino, David Robert C., i Aristeo R. Cruz. Obligations & Contracts. Third edition. Quezon City: Central Book Supply, Inc, 2020.

Cita MLA (9th ed.)

Aquino, David Robert C., i Aristeo R. Cruz. Obligations & Contracts. Third edition. Central Book Supply, Inc, 2020.