APA

(1977). Advanced exercises in practical english 1 und 2: 2 bde. London: .

Chicago

1977. Advanced exercises in practical english 1 und 2: 2 bde. London: .

Harvard

(1977). Advanced exercises in practical english 1 und 2: 2 bde. London: .

MLA

Advanced exercises in practical english 1 und 2: 2 bde. London: . 1977.