Peel 219 : Lefroy, John Henry (Sir) (1817-1890) [détails]; Richardson, John (Sir) (1787-1865) [détails]; Younghusband, Charles Wright (1821-1899) [détails]. Magnetical and meteorological observations at Lake Athabasca and Fort Simpson by J.H. Lefroy and at Fort Confidence in Great Bear Lake by John Richardson. London : Published for Her Majesty's Stationery Office by Longman, Brown, Green, and Longmans, 1855. .
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