TY - JOUR TI - P 14. JO - Canadian mathematical bulletin PY - 1959 SP - 43 EP - 44 VL - 2 IS - 1 UR - http://geodesic.mathdoc.fr/articles/10.1017/S0008439500024899/ DO - 10.1017/S0008439500024899 ID - 10_1017_S0008439500024899 ER -