TY  - JOUR
AU  - Emmanuel Preissmann
TI  - On the length of the period of ...d.
JO  - Forum mathematicum
PY  - 1994
SP  - 137
EP  - 138
VL  - 6
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/FORUM_1994__6_3_141729/
ID  - FORUM_1994__6_3_141729
ER  -