TY - JOUR TI - BCM volume 62 Issue 4 Cover and Front matter JO - Canadian mathematical bulletin PY - 2019 SP - f1 EP - f2 VL - 62 IS - 4 UR - http://geodesic.mathdoc.fr/articles/10.4153/S0008439519000584/ DO - 10.4153/S0008439519000584 ID - 10_4153_S0008439519000584 ER -