Não informado. (1921). World tanker fleet review. John I. Jacobs and Company.
Chicago-viite (17. p.)Não informado. World Tanker Fleet Review. London: John I. Jacobs and Company, 1921.
MLA-viite (8. p.)Não informado. World Tanker Fleet Review. John I. Jacobs and Company, 1921.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.