Hurd 1924, Ch V. Hurd, Archibald (1924). "Chapter V: Merchant Seamen and the Blockade". The Merchant Navy. History of the Great War based on Official Documents by direction of the Historical Section of the Committee of Imperial Defence. Vol. II (online scan ed.). London: John Murray. pp. 100–156. OCLC669068495 – via Naval-history.net.
Hurd 1924, Ch V. Hurd, Archibald (1924). "Chapter V: Merchant Seamen and the Blockade". The Merchant Navy. History of the Great War based on Official Documents by direction of the Historical Section of the Committee of Imperial Defence. Vol. II (online scan ed.). London: John Murray. pp. 100–156. OCLC669068495 – via Naval-history.net.