एपीए उद्धरण

Ashton, S. Pet preliminary English test practice tests plus 2 with key. New York: Longman.

शिकागो स्टाइल उद्धरण

Ashton, Sharon. Pet Preliminary English Test Practice Tests Plus 2 With Key. New York: Longman.

एमएलए उद्धरण

Ashton, Sharon. Pet Preliminary English Test Practice Tests Plus 2 With Key. New York: Longman.