APA
Palmer H. E., . (1923). The oral method of teaching languages. Cambridge: W. Heffer & Sons Ltd.
Chicago
Palmer Harold E, . 1923. The oral method of teaching languages. Cambridge: W. Heffer & Sons Ltd.
Harvard
Palmer H. E., . (1923). The oral method of teaching languages. Cambridge: W. Heffer & Sons Ltd.
MLA
Palmer Harold E, . The oral method of teaching languages. Cambridge: W. Heffer & Sons Ltd. 1923.