Drummond, Peter (2007). Scottish hill names: The origin and meaning of the names of Scotland's hills and mountains (2nd ed.). Glasgow; Leicester: Scottish Mountaineering Trust; Distributed by Cordee. p. 25. ISBN978-0-907521-95-2.
"Legend (INT Symbology)". Merenkulku.fi. Helsinki: Finnish Transport Agency and Finnish Transport Safety Agency (TraFi). Archived from the original(PDF) on 26 January 2012. Three-language key to reading Finnish navigation charts.
fredericknewspost.com
Kay, Mike; The Frederick County Forestry Board (17 January 2016). "Building of cairns has long history". The Frederick News-Post. Retrieved 20 September 2022.
"Legend (INT Symbology)". Merenkulku.fi. Helsinki: Finnish Transport Agency and Finnish Transport Safety Agency (TraFi). Archived from the original(PDF) on 26 January 2012. Three-language key to reading Finnish navigation charts.