%0 Journal Article %A A. Yanushauskas %T Direct methods for studying the singularities of the sums of Laplace series that lie on the boundary of a ball of convergence %J Differencialʹnye uravneniâ %D 1977 %P 344-357 %V 13 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/item/DE_1977_13_2_a13/ %G ru %F DE_1977_13_2_a13