Strongly correlated electron systems and quantum magnetism

Abstract

We dedicate this special issue to Andrij Shvaika and Oleg Derzhko in celebration of their 60th anniversaries. Both Andrij and Oleg have been colleagues throughout their lives, as illustrated in the photos, one showing them during their primary school years and the other showing them at a recent conference held in Lviv in 2019. Andrij and Oleg have worked at the same Institute for decades and are also both Associate Editors of the \textit{Condensed Matter Physics} journal. It is fitting to celebrate the two of them together in this special issue. The selected contributions cover a wide range of topics closely related to the leading scientific interests of both jubilees to acknowledge their unique and valuable contributions to science.