For further reading:

1) Canada, Department of Energy, Mines and Resources, 1974: The National Atlas of Canada. Canada: Department of Energy, Mines and Resources.
2) Davidson, Gordon C., 1918: The North West Company. Berkeley: University of California Press.
3) Freeman, Donald B. & Frances L. Dungey, 1981: "A spatial duopoly: competition in the western Canadian fur trade, 1770-1835." Journal of Historical Geography 7 (3): 252-270
4) Lytwyn, Victor P., 1986: The Fur Trade of the Little North: Indians, Pedlars, and Englishmen East of Lake Winnipeg, 1760-1821. Winnipeg: University of Winnipeg/Rupert's Land Research Centre.
5) Moodie, Wayne D., 1987: "The trading post settlement of the Canadian Northwest, 1774-1821." Journal of Historical Geography 13 (4) : 360-74.
6) Morse, Eric W., 1979: Fur Trade Canoe Routes of Canada, Then and Now. Ottawa: Minister of Supply and Services.
7) Ray, Arthur J., 1988: The Hudson's Bay Company and Native People, pp 335-50, IN W. B. Washburn, ed., Handbook of North American Indians, 4: History of Indian-White Relations. Washington: Smithsonian Institution.