00312nam a2200121Ia 4500020001500000082001900015100002000034245006200054260003600116300002800152500000500180700000500185  a376437019X  a510.9bB511.EI  aBerinde, Vasile  aExploring, investigating and discovering in mathematicsb  aBostonbBirkhauser Verlagc2004  axix, 246p. Bibl. Index.  a  a