%0 Journal Article %A A. A. Agrachev %A R. V. Gamkrelidze %T The exponential representation of flows and the chronological calculus %J Sbornik. Mathematics %D 1979 %P 727-785 %V 35 %N 6 %U http://geodesic.mathdoc.fr/item/SM_1979_35_6_a0/ %G en %F SM_1979_35_6_a0