Fraenkel, Aviezri S. Ratwyt/ Aviezri S. Fraenkel. - Washington D. C.: Mathematical Association of America, ŠJul 2012-Sept 2015. - v43 n2, pages 160-164: illustrations; 28 cm. ISSN: 0746-8342 Subjects--Topical Terms: Arithmetic. Dewey Class. No.: DPer 510.5 C697 Jan 2012-Sept 2015 v. 43 & 46, n. 1-4