In the continuation of my research on polyhedra in African cultures, I have the pleasure to announce the publication of the paper: African dance rattle capsules from Cameroon to Madagascar, from Somalia to Mozambique: Plaiting a symmetric, nonahedral shape.
In the international journal «Visual Mathematics» (Volume 14, No. 3), published online by the Mathematical Institute of the Serbian Academy of Sciences and Arts, Belgrade. The paper is available at: http://www.mi.sanu.ac.rs/vismath/gerdesnovember2012/nonahedral.pdf
Abstract: The following paper presents examples of dance rattles from several parts of Africa: from Cameroon in the West-Central Africa, from Somalia and Kenya in Eastern Africa, and from Madagascar and Mozambique in Southern Africa. The capsules of these rattles are plaited in a similar way. They display a nonahedral shape (nine faces) and each capsule is made from only one strip of a leaf. A plaited capsule can be understood as an alternating knot, precisely as knot 940 in the international knot table. The paper shows how to weave a strip of cardboard paper to produce the nonahedral shape.
Professor of Mathematics, Vice-President for Southern Africa, African Academy of Sciences
Chairman, AMU Commission for the History of Mathematics in Africa
President, International Studygroup for Ethnomathematics
Former Rector / President, Pedagogical University, Mozambique