@book{238066,
	author = {Alsina, Claudi. and Sikorska, Justyna. and ebrary, Inc.},
	title = {Norm derivatives and characterizations of inner product spaces},
	publisher = {World Scientific,},
	year = {c2010.},
	address = {Singapore :},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10422427}
}