APA (7th ed.) Citation

Nock, O. S. (1973). Underground railways of the world / (by) O.S. Nock. A. and C. Black.

Chicago Style (17th ed.) Citation

Nock, O. S. Underground Railways of the World / (by) O.S. Nock. London: A. and C. Black, 1973.

MLA (9th ed.) Citation

Nock, O. S. Underground Railways of the World / (by) O.S. Nock. A. and C. Black, 1973.

Warning: These citations may not always be 100% accurate.