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3. V. I. Zorkal’tsev, “Octahedral and Euclidean projections of a point to a linear manifold,” Proc. Steklov Inst. Math. 284, Suppl. 1, 185–197 (2014).
4. V. I. Zorkal’tsev, “Projections of a point onto a polyhedron,” Vychisl. Mat. Mat. Fiz. 53 (1), 1–16 (2013).
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