"The Canadian Hydrographic Service"(PDF). Ontario Professional Surveyor. 32 (4). Association of Ontario Land Surveyors: 22–23. 1989. Archived from the original(PDF) on 6 October 2015. Retrieved 6 October 2015.
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"The Canadian Hydrographic Service"(PDF). Ontario Professional Surveyor. 32 (4). Association of Ontario Land Surveyors: 22–23. 1989. Archived from the original(PDF) on 6 October 2015. Retrieved 6 October 2015.
