APA

Lucas J., . (1967). The principles of politics. Gran Bretana: Oxford University Press.

Chicago

Lucas J.R, . 1967. The principles of politics. Gran Bretana: Oxford University Press.

Harvard

Lucas J., . (1967). The principles of politics. Gran Bretana: Oxford University Press.

MLA

Lucas J.R, . The principles of politics. Gran Bretana: Oxford University Press. 1967.