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[2] ČULÍK K.:
On semantics of programming languages, Automatentheorie und Formale Sprachen. editors J. Dörr - G. Hotz, Bibliographisches Institut, Mannheim - Wien - Zürich 1970, 291-303.
MR 0421123
[3] ČULÍK K.: On sequential and non-sequential machines, and their relation to the computation in computers. (mimeographed in IFIP-WG 2. 2 Bulletin, No. 6, February 1970).