Three stages of the NICA accelerator complex V. D. Kekelidze, R. Lednicky, V. A. Matveev, I. N. Meshkov, A. S. Sorin and G. V. Trubnikov Eur. Phys. J. A, 52 8 (2016) 211 Published online: 08 August 2016 DOI: 10.1140/epja/i2016-16211-2