Skrypnik, W. I. “Equilibrium in Quantum Systems of Particles With Magnetic Interaction”. Ukrains’kyi Matematychnyi Zhurnal 47, no. 12 (December 25, 1995): 1686–1691. Accessed April 7, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/5562.