Nilsen, Thomas, Per Magnus, and Ragnhild Ørstavik. “Maternal Body Composition in Relation to Twinning”. Norsk Epidemiologi 26, no. 1-2 (July 20, 2016). Accessed April 19, 2024. https://www.ntnu.no/ojs/index.php/norepid/article/view/2019.