APA (7. basım) Alıntı

Gray, E., & O'Sullivan, N. Practice Tests for the PET 1 Preliminary English Test: Class CDs. Express Publishing.

Chicago Style (17. basım) Atıf

Gray, Elisabeth, ve Neil O'Sullivan. Practice Tests for the PET 1 Preliminary English Test: Class CDs. Newbury: Express Publishing.

MLA (8th ed.) Atıf

Gray, Elisabeth, ve Neil O'Sullivan. Practice Tests for the PET 1 Preliminary English Test: Class CDs. Express Publishing.