In addition, the help of Mr. Marek Kaźmierczak in the final book preparation is
highly appreciated.
Finally, we would like to acknowledge the support of the Russian Science
Foundation RSF No, grant and Polish National Science Centre under the grant
OPUS 14 No. 2017/27/B/ST8/01330.
Lodz, Poland
Jan Awrejcewicz
Saratov, Russia
Anton V. Krysko
Saratov, Russia
Maxim V. Zhigalov
Saratov, Russia
Vadim A. Krysko
viii
Preface