APA

Keller E., Warner S. T., . (1988). Conversation Gambits. London: Language Teaching Publications.

Chicago

Keller E, Warner S T, . 1988. Conversation Gambits. London: Language Teaching Publications.

Harvard

Keller E., Warner S. T., . (1988). Conversation Gambits. London: Language Teaching Publications.

MLA

Keller E, Warner S T, . Conversation Gambits. London: Language Teaching Publications. 1988.