TY  - JOUR
AU  - Takens, Floris
TI  - The Lusternik-Schnirelman categories of a product space
JO  - Compositio Mathematica
PY  - 1970
SP  - 175
EP  - 180
VL  - 22
IS  - 2
PB  - Wolters-Noordhoff Publishing
UR  - http://archive.numdam.org/item/CM_1970__22_2_175_0/
LA  - en
ID  - CM_1970__22_2_175_0
ER  -