%0 Journal Article %A Miloje Rajović %A Rade Stojiljković %T The first, the second, and the third Liouville formula and periodical solutions of linear differential equation of the second order %J Kragujevac Journal of Mathematics %D 2007 %P 131 %V 30 %I mathdoc %U http://geodesic.mathdoc.fr/item/KJM_2007_30_a8/ %G en %F KJM_2007_30_a8