APA (7th ed.) Citation

ETHERTON, A. (1976). Contact 4: A secondary english course. -- Ed. revisi. Longman.

Chicago Style (17th ed.) Citation

ETHERTON, A.R.B. Contact 4: A Secondary English Course. -- Ed. Revisi. Kuala Lumpur: Longman, 1976.

MLA (9th ed.) Citation

ETHERTON, A.R.B. Contact 4: A Secondary English Course. -- Ed. Revisi. Longman, 1976.