@book{56461,
	author = {Marshall, Murray.},
	title = {Positive polynomials and sums of squares /},
	publisher = {American Mathematical Society,},
	year = {cop. 2008.},
	series = {Mathematical Surveys and Monographs,},
	address = {Providence :},
	url = {http://koha.tu.koszalin.pl/cgi-bin/koha/opac-detail.pl?biblionumber=56461}
}