Cita APA (7a ed.)

Summers, R. S., & Hillman, R. A. (1992). Contract and related obligation: Theory, doctrine and practice (2nd ed.). West Publishing.

Cita Chicago Style (17a ed.)

Summers, Robert S., y Robert A. Hillman. Contract and Related Obligation: Theory, Doctrine and Practice. 2nd ed. St. Paul [Minn.]: West Publishing, 1992.

Cita MLA (9a ed.)

Summers, Robert S., y Robert A. Hillman. Contract and Related Obligation: Theory, Doctrine and Practice. 2nd ed. West Publishing, 1992.