Cita APA (7a ed.)

Heaton, J. (1978). Key to using prepositions and particles: Workbooks. Longman.

Cita Chicago Style (17a ed.)

Heaton, J.B. Key to Using Prepositions and Particles: Workbooks. London: Longman, 1978.

Cita MLA (9a ed.)

Heaton, J.B. Key to Using Prepositions and Particles: Workbooks. Longman, 1978.