Não informado. (2004). Steam Engineer. John D. Troup.
Chicago (17e ed.) BronvermeldingNão informado. Steam Engineer. London: John D. Troup, 2004.
MLA (8e ed.) BronvermeldingNão informado. Steam Engineer. John D. Troup, 2004.
Let op: Deze citaties zijn niet altijd 100% accuraat.