Lac de la Source is a Lake located in Rivière-Mistassini; Maria-Chapdelaine, Quebec.

• Latitude: 49° 38' 34'' North   (decimal: 49.6428330)
• Longitude: 72° 47' 16'' West   (decimal: -72.7878877)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Rivière-Mistassini; Maria-Chapdelaine
• Atlas of Canada Locator Map: Lac de la Source
• GPS Coordinate Locator Map: Lac de la Source Lat/Long