1. A. I. Dyagelev, “Development and examination of the high-efficiency flow part of the ÉPN-6 deep-well pump,” in: Hydraulic Engineering [in Russian], Mashinostroenie, Moscow-Leningrad (1965), pp. 45–52.
2. USSR Author's Cert. No. 922323, A deep-well centrifugal pump; Byull. Izobr., No. 15 (1982).
3. USSR Author's Cert. No. 1008503, A stage of deep-well centrifugal pump; Byull. Izobr., No. 12 (1983).