Gotaas, Geir, and Nicholas J.C. Tyler. “Faeces is a reliable source of body water for measuring tritium in reindeer in summer and in winter”. Rangifer 15, no. 2 (January 1, 1995): 63–70. Accessed April 24, 2024. https://septentrio.uit.no/index.php/rangifer/article/view/1168.