@book{13568,
	author = {Gilbarg, David and Trudinger, Neil S. and Trudinger, Neil S. ; jt. auth.},
	title = {Elliptic partial differential equations of second order},
	publisher = {Springer-Verlag},
	year = {2001},
	series = {Classics in Mathematics},
	address = {Berlin},
	edition = {reprint of the 1998}
}