Horton , T. W., Blum , J. D., Xie , Z., Hren , M., & Chamberlain , C. P. (2009). Stable isotope food-web analysis and mercury biomagnification in polar bears (Ursus maritimus). Polar Research, 28(3), 443-454. https://doi.org/10.3402/polar.v28i3.6135