O. I.Zorina, T. V.Neskuba, O. M.Mkrtychyan, and V. A.Volokhov, “Benchmarking of the Transport Market with Hierarchical Clustering of Rail Companies”, IJET, vol. 7, no. 4.3, pp. 557–562, Sep. 2018, doi: 10.14419/ijet.v7i4.3.19956.