@book{28399,
	author = {Symposium on "Partial Differential Equations", Karl-Weierstrass-Institute of Mathematics, Berlin, 25 - 29 April 1988 and Schulze, Bert-Wolfgang ; ed.},
	title = {Partial differential equations},
	publisher = {BSB B. G. Teubner Verlagegesellechaft},
	year = {1989},
	address = {Leipzig}
}