Media type: E-Article Title: Elementary Definability of the Class of Universal Planar Automata in the Class of Semigroups Contributor: Molchanov, V. A. imprint: Pleiades Publishing Ltd, 2019 Published in: Siberian Mathematical Journal Language: English DOI: 10.1134/s0037446619060168 ISSN: 0037-4466; 1573-9260 Keywords: General Mathematics Origination: Footnote: