Cita APA (7th ed.)

Smart, J. D., & J.M. Swanson. A Promise to keep. Westminster Press.

Cita Chicago (17th ed.)

Smart, James D., i J.M. Swanson. A Promise to Keep. Philadelphia: Westminster Press.

Cita MLA (9th ed.)

Smart, James D., i J.M. Swanson. A Promise to Keep. Westminster Press.