@book{6896,
	author = {Lehto, Olli. and Virtanen, K. I.,},
	title = {Quasiconformal mappings in the plane},
	publisher = {Springer,},
	year = {1973.},
	address = {Berlin,},
	edition = {2nd ed.},
	note = {Translation of Quasikonforme Abbildungen.}
}