"arres, frank . "
differecial equations: / frank.. arres - 2 ed. - usa : macgraw-hill 1972. - ", 295p.; 27 cm."
515. 352 ayr
differecial equations: / frank.. arres - 2 ed. - usa : macgraw-hill 1972. - ", 295p.; 27 cm."
515. 352 ayr