TY - JOUR AU - N. Satimov TI - The composition of a differential equation from its solutions, and the proof of a lemma of L. S. Pontrjagin JO - Differencialʹnye uravneniâ PY - 1978 SP - 1208 EP - 1214 VL - 14 IS - 7 UR - http://geodesic.mathdoc.fr/item/DE_1978_14_7_a7/ LA - ru ID - DE_1978_14_7_a7 ER -