Dyfyniad APA

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

Dyfyniad Arddull Chicago

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

Dyfyniad MLA

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

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.