1. A. V. Aho, J. E. Hopcroft, and J. D. Ullman, The Design and Analysis of Computer Algorithms, Addison-Wesley Longman Publishing Co., Inc., Reading, Mass. (1974).
2. A. I. Ivaneshkin, “A new approach to operating with undirected trees,” Cybern. Syst. Analysis, Vol. 57, No. 1, 124–132 (2021). https://doi.org/10.1007/s10559-021-00335-z.
3. A. I. Ivaneshkin, “The solution of the question of the isomorphism of non-oriented trees by the method of generating isomorphic structures,” J. Autom. Inform. Sci., Vol. 52, Iss. 8, 68–79 (2020).
4. A. I. Ivaneshkin, “Universal multifunctional tools for polycomponent structures of undirected trees and isolated vertices,” in: Proc. of the 9th Intern. Conf. “Informatics and Computer Technics Problems” (PICT-2020) (Chernivtsi, Ukraine, 28–31 October, 2020), Chern. Nats. Un-t, Chernivtsi (2020), pp. 95–98.