https://www.titanicbelfast.com/history-of-titanic/ship-fact-files/oceanic-i-fact-file/
Discover more about RMS Titanic, SS Nomadic and the other Olympic Class Liners with Titanic Belfast's Ship Fact Files.
fact fileoceanicshipfileshistory
https://www.cambridge.org/core/journals/law-and-history-review/article/oceanic-mobility-and-the-empire-of-the-pass-system/BD64E93B3FCDE195B7DAA56276060896
Oceanic Mobility and the Empire of the Pass System - Volume 41 Issue 3
pass systemoceanicmobilityempirelaw