Peel 217 : Lefroy, John Henry (Sir) (1817-1890) [détails]. Diary of a magnetic survey of a portion of the Dominion of Canada, chiefly in the North-Western Territories, executed in the years 1842-1844. London : Longmans, Green & Co, 1883. .
Peel 217 : Lefroy, John Henry (Sir) (1817-1890) [détails]. Diary of a magnetic survey of a portion of the Dominion of Canada, chiefly in the North-Western Territories, executed in the years 1842-1844. London : Longmans, Green & Co, 1883. .