TY - JOUR AU - I. A. Bakhtin AU - M. A. Krasnosel'skii TI - On the theory of equations with concave operators JO - Doklady Akademii Nauk PY - 1958 SP - 17 EP - 20 VL - 123 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/DAN_1958_123_1_a2/ LA - ru ID - DAN_1958_123_1_a2 ER -