Cita APA (7th ed.)

Peter D.Riley. (2019). Cambridge Checkpoint Science Student's Book 1 (2nd.). Hodder Education; Stu New edition (2011-05-27).

Cita Chicago (17th ed.)

Peter D.Riley. Cambridge Checkpoint Science Student's Book 1. 2nd. Hodder Education; Stu New edition (2011-05-27), 2019.

Cita MLA (9th ed.)

Peter D.Riley. Cambridge Checkpoint Science Student's Book 1. 2nd. Hodder Education; Stu New edition (2011-05-27), 2019.