Gjertsen, Jan-Erik, Jonas Fevang, Tarjei Vinje, Lars Birger Engesæter, Kjersti Steindal, and Ove Furnes. “The Norwegian Hip Fracture Register / Nasjonalt Hoftebruddregister”. Norsk Epidemiologi 16, no. 2 (October 9, 2009). Accessed July 5, 2024. https://www.ntnu.no/ojs/index.php/norepid/article/view/190.