Fushchich, V. I., V. I. Lagno, and R. Z. Zhdanov. “Reduction of the Self-Dual Yang-Mills Equations I. Poincaré Group”. Ukrains’kyi Matematychnyi Zhurnal 47, no. 4 (April 25, 1995): 456–462. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/5442.