Glushchenko, A. A., et al. “V. G. Georgii Mykolaiovych Polozhyi (on His 90th Birthday)”. Ukrains’kyi Matematychnyi Zhurnal, vol. 56, no. 4, Apr. 2004, pp. 560-1, https://umj.imath.kiev.ua/index.php/umj/article/view/3776.