Ivanov, I. I.; Ivanova, G. A.; Kondrat'ev, V. N.; Polinkovskii, I. A. (1991-01-01). "Increase of the efficiency of small hydroelectric stations". Hydrotechnical Construction. 25 (1): 1–4. doi:10.1007/BF01428128. ISSN1570-1468. S2CID108957913.
Ivanov, I. I.; Ivanova, G. A.; Kondrat'ev, V. N.; Polinkovskii, I. A. (1991-01-01). "Increase of the efficiency of small hydroelectric stations". Hydrotechnical Construction. 25 (1): 1–4. doi:10.1007/BF01428128. ISSN1570-1468. S2CID108957913.
Ivanov, I. I.; Ivanova, G. A.; Kondrat'ev, V. N.; Polinkovskii, I. A. (1991-01-01). "Increase of the efficiency of small hydroelectric stations". Hydrotechnical Construction. 25 (1): 1–4. doi:10.1007/BF01428128. ISSN1570-1468. S2CID108957913.