Gray, E., & O'Sullivan, N. Practice Tests for the PET 1 Preliminary English Test: Class CDs. Express Publishing.
Style de citation Chicago (17e éd.)Gray, Elisabeth, et Neil O'Sullivan. Practice Tests for the PET 1 Preliminary English Test: Class CDs. Newbury: Express Publishing.
Style de citation MLA (8e éd.)Gray, Elisabeth, et Neil O'Sullivan. Practice Tests for the PET 1 Preliminary English Test: Class CDs. Express Publishing.
Attention : ces citations peuvent ne pas être correctes à 100%.