Παραπομπή APA

Heard, B. E. (1969). Pathology of chronic bronchitis and emphysema.

Παραπομπή Chicago Style

Heard, Brian Edyvean. Pathology of Chronic Bronchitis and Emphysema. 1969.

Παραπομπή MLA

Heard, Brian Edyvean. Pathology of Chronic Bronchitis and Emphysema. 1969.