1. Yu. G. Stoyan and O. A. Emets,Theory and Methods of Euclidean Combinatorial Optimization [in Russian], Institute of System Investigations in Education, Kiev (1993).
2. Yu. G. Stoyan,Some Properties of Special Combinatorial Sets [in Russian], Preprint No. 85, Institute of Problems of Machine Building of the Academy of Sciences of Ukraine, Kharkov (1980).
3. O. A. Emets,Theory and Methods of Combinatorial Optimization on Euclidean Sets in Geometric Projection [in Ukrainian], Author’s Abstract of the Doctoral-Degree Thesis, Kiev (1997).
4. O. A. Emest, “On optimization of convex functions on a Euclidean combinatorial set of polypermutations,”Zh. Vychisl. Mat. Mat. Fiz., No. 6, 855–869 (1994).
5. O. A. Emets, “On extremal properties of nondifferentiable convex functions on a Euclidean set of combinations with repetitions”Ukr. Mat. Zh.,46, No. 6. 680–691 (1994).