Preface
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This volume is dedicated to Victor Selivanov on the occasion of his 70th birthday. It consists of 5 research articles by 7 authors, as well as our joint article with Dieter Spreen on the main scientific achievements of Victor Selivanov, in the general context of the development of computability theory, which he significantly contributed to.
We are deeply grateful to everyone who helped us accomplish this volume: especially the authors, the editors, and the referees. We would also like to thank all the participants of the Special Session in Honor of the 70th Birthday of Victor Selivanov, which took place during the Fourth Workshop on Digitalization and Computable Models (WDCM-2022), Novosibirsk and Kazan, Russia / online, during October 27–29, 2022. Most of the papers of the volume are contributed by the participants of this session.