Παραπομπή σε μορφή APA (7η εκδ.)

Hensen, H. C. (1997). Tug use in port: A practical guide covering tug types, performance, shiphandling, safety, training and escort operations. Nautical Institute.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Hensen, Henk Captain. Tug Use in Port: A Practical Guide Covering Tug Types, Performance, Shiphandling, Safety, Training and Escort Operations. London: Nautical Institute, 1997.

Παραπομπή σε μορφή MLA (9th εκδ.)

Hensen, Henk Captain. Tug Use in Port: A Practical Guide Covering Tug Types, Performance, Shiphandling, Safety, Training and Escort Operations. Nautical Institute, 1997.