TY - JOUR AU - R. A. Syunyaev TI - The necessity of a neutral hydrogen period in the evolution of the Universe JO - Doklady Akademii Nauk PY - 1968 SP - 45 EP - 47 VL - 179 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/DAN_1968_179_1_a10/ LA - ru ID - DAN_1968_179_1_a10 ER -