Furu, Kari, Ellen Barth Aares, Vidar Hjellvik, and Øystein Karlstad. 2021. “Hormonal Contraceptive Use in Norway, 2006-2020, by Contraceptive Type, Age and County: A Nationwide Register-Based Study”. Norsk Epidemiologi 29 (1-2). https://doi.org/10.5324/nje.v29i1-2.4046.