APA (7th ed.) Citation

Christophersen, P. (1981). An english phonetics course. Longman Group.

Chicago Style (17th ed.) Citation

Christophersen, Paul. An English Phonetics Course. Longman Group, 1981.

MLA (8th ed.) Citation

Christophersen, Paul. An English Phonetics Course. Longman Group, 1981.

Warning: These citations may not always be 100% accurate.