000 00364 a2200157 4500
001 1541
011 _a00131954
090 _a1541
100 _a20170516 frey50
101 _afre
102 _aFR
200 _aEducational studies in mathematics ESM
207 _avol 17 n° 2 may 1986
210 _aHolland
_cD. Reidel publishing company
215 _d24
099 _tSER
500 _aESM