APA

humphrey p., . (1993). Working Together. london: evans Brpthers limited.

Chicago

humphrey paul, . 1993. Working Together. london: evans Brpthers limited.

Harvard

humphrey p., . (1993). Working Together. london: evans Brpthers limited.

MLA

humphrey paul, . Working Together. london: evans Brpthers limited. 1993.