APA

Harrison, . (1971). Principles of Internal Medicine. London: McGraw - Hill Book Co.

Chicago

Harrison, . 1971. Principles of Internal Medicine. London: McGraw - Hill Book Co.

Harvard

Harrison, . (1971). Principles of Internal Medicine. London: McGraw - Hill Book Co.

MLA

Harrison, . Principles of Internal Medicine. London: McGraw - Hill Book Co. 1971.