APA (7th ed.) Citation

Liffen, J. (2004). Mail tubes: The modern communications system of the nineteenth century.

Chicago Style (17th ed.) Citation

Liffen, John. Mail Tubes: The Modern Communications System of the Nineteenth Century. 2004.

MLA (9th ed.) Citation

Liffen, John. Mail Tubes: The Modern Communications System of the Nineteenth Century. 2004.

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