@book{14665,
	author = {Sommerfeld, Arnold and Straus, Ernst G.},
	title = {Partial differential equation in physics; lectures on the theoretical physics; v. 6},
	publisher = {Academic Press,},
	year = {1967},
	series = {Pure and Applied Mathematics},
	address = {New York:},
	note = {"Lectures on Theoretical Physics, v. 6". "Translated by Ernst G. Straus".}
}