Letter (hand-written) Request for an opinion on the paper by V. Sabelfeld "The tree equivalence of linear recursive schemata in polynomial-time decidable"; asks for the references to the up-to-date works on the subject of Ershov's presentation at the MFCS'81 Conference Date: 14.05.1981 Original document language: English Authors: Andrei Petrovich Ershov Organizations: IBM, Thomas J. Watson Research Center Persons: Viktor K. Sabelfeld Addressee: Barry K. Rosen
