Cogwheels of the mind : the story of Venn diagrams / A.W.F. Edwards ; forew. by Ian Stewart. - Baltimore ; London : John Hopkins Univ. press, c.2004. - xvi, 110 p. : fig., 1 fr. l., portr. ; 24 cm.см.. - ბიბლიოგრ.: გვ. 105-108. - ISBN 0-8018-7434-3[MFN: 45898]