TY - JOUR AU - E. I. Bravyi TI - On positive periodic solutions of first order functional differential equations JO - Izvestiya Instituta Matematiki i Informatiki Udmurtskogo Gosudarstvennogo Universiteta PY - 2015 SP - 21 EP - 28 VL - 46 IS - 2 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/IIMI_2015_46_2_a2/ LA - ru ID - IIMI_2015_46_2_a2 ER -