Dr. Vincent H. Malmström. Professor Emeritus of Geography. "Norway Before the Vikings"(PDF). Dartmouth College. Archived from the original(PDF) on February 4, 2012. Retrieved August 15, 2016.
snl.no
Frans-Arne Stylegar. "Fosnakomplekset". Store norske leksikon. Retrieved August 15, 2016.
Dr. Vincent H. Malmström. Professor Emeritus of Geography. "Norway Before the Vikings"(PDF). Dartmouth College. Archived from the original(PDF) on February 4, 2012. Retrieved August 15, 2016.