APA (7e ed.) Bronvermelding

Não informado. (2011). Railway Signaling. Simmons Boardman Publishing.

Chicago (17e ed.) Bronvermelding

Não informado. Railway Signaling. Chicago, Ill: Simmons Boardman Publishing, 2011.

MLA (8e ed.) Bronvermelding

Não informado. Railway Signaling. Simmons Boardman Publishing, 2011.

Let op: Deze citaties zijn niet altijd 100% accuraat.