000 00354nam a2200145Ia 4500
020 _a0080165826
082 _b2162
_a510
100 _a"H.W.Clayton"
245 2 _aA Natural Approach to Mathematics
260 _b,Pergamon Press
_aGreat Britain
_c1972
300 _a248
944 _cBK
999 _c630732
_d630732