TY  - JOUR
AU  - Levitz, Hilbert
TI  - The Cartesian product of sets and the Hessenberg natural product of ordinals
JO  - Czechoslovak Mathematical Journal
PY  - 1979
SP  - 353
EP  - 358
VL  - 29
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1979.101618/
DO  - 10.21136/CMJ.1979.101618
LA  - en
ID  - 10_21136_CMJ_1979_101618
ER  -