@book{35577,
	author = {Christensen, Ole. and Christensen, Khadija L. and SpringerLink (Online service)},
	title = {Approximation Theory},
	publisher = {Birkhäuser Boston :},
	year = {2005.},
	series = {Applied and Numerical Harmonic Analysis},
	address = {Boston, MA :},
	url = {http://dx.doi.org/10.1007/978-0-8176-4448-2}
}