%0 Journal Article %A B. I. Losev %A I. E. El'piner %A A. N. Melnikova %T On the halogen treatment of coals under the action of ultrasonic waves %J Doklady Akademii Nauk %D 1957 %P 372-374 %V 114 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DAN_1957_114_2_a31/ %G ru %F DAN_1957_114_2_a31