APA

Lichtheim G., . (1972). Europe in the twentieth century. New York: Praeger Publishers.

Chicago

Lichtheim George, . 1972. Europe in the twentieth century. New York: Praeger Publishers.

Harvard

Lichtheim G., . (1972). Europe in the twentieth century. New York: Praeger Publishers.

MLA

Lichtheim George, . Europe in the twentieth century. New York: Praeger Publishers. 1972.