Lysaker, Dagny Iren, B.R. Pettersen, O. Mathisen, and Dag Solheim. “The Norwegian Height System NN1954 Revisited”. Nordic Journal of Surveying and Real Estate Research 3, no. 1 (February 17, 2006). Accessed June 29, 2024. https://journal.fi/njs/article/view/1665.