00610nam a2200181Ia 4500082001800000100004300018245007400061260003100135300002000166490005200186500000500238690000600243700003500249952010000284964001700384921001000401999001700411  a516bAb141.TG  aAbolson, Harold and Disessa, Andrea A.  aTurtle geometry; the computer as a medium for exploring mathematicsb  aCambridgebMIT Pressc1981  axx, 477p. Index  aThe MIT Press series in artificial intelligence  a  a   aDisessa, Andrea A. ; jt. auth.  00104070aISIbISId1998-09-17l0o516 Ab141.TGpDP18176r2019-02-14 00:00:00w2019-02-14yBK  abcdefg  a11749  c11749d11749