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Harper, Douglas. "dam". Online Etymology Dictionary. Douglas Harper. Retrieved 14 December 2022.
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"16. Cofferdams". Underwater Ship Husbandry Manuals(PDF) (Revision 0, Change H ed.). 15 November 2011. S0600-AA-PRO-160. This article incorporates text from this source, which is in the public domain.
U.S. Navy Salvage Manual(PDF). Vol. 1: Strandings, Harbor Clearance and Afloat Salvage S0300-A6-MAN-010. United States. Navy Department. Supervisor of Salvage and Diving. 31 May 2013. Archived(PDF) from the original on 5 April 2023. Retrieved 28 March 2023.
U.S. Navy Salvage Manual(PDF). Vol. 1: Strandings, Harbor Clearance and Afloat Salvage S0300-A6-MAN-010. United States. Navy Department. Supervisor of Salvage and Diving. 31 May 2013. Archived(PDF) from the original on 5 April 2023. Retrieved 28 March 2023.