TY  - JOUR
AU  - Halter-Koch, Franz
TI  - Letter to the Editor
JO  - Canadian mathematical bulletin
PY  - 1973
SP  - 299
EP  - 299
VL  - 16
IS  - 3
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1973-050-x/
DO  - 10.4153/CMB-1973-050-x
ID  - 10_4153_CMB_1973_050_x
ER  -