Contradictions and narrowness of views in "The fables of Ishango, or the   irresistible temptation of mathematical fiction", answers and updates (in   English and in French)
  We answer to criticisms of O. Keller about our interpretation work on the Ishango rod, the oldest mathematical tool of humankind. Our hypothesis, that is widely accepted, is that this prehistoric rod is the first mankind manifestation of a basic arithmetic intention, with simple arithmetic operations and possibly showing passages between 10 and 12 bases. 
Vladimir Pletser and Dirk Huylebrouck
math.HO