@book{14770,
	author = {KLIFFORD, A. and PRESTON, G.},
	title = {Algebraiceskaja teorija polugrupp :},
	year = {1972.},
	address = {Moskwa,},
	url = {http://koha.tu.koszalin.pl/cgi-bin/koha/opac-detail.pl?biblionumber=14770}
}