TY  - JOUR
AU  - Hołubowski, Waldemar
TI  - An inverse matrix of an upper triangular matrix can be lower triangular
JO  - Discussiones Mathematicae. General Algebra and Applications
PY  - 2002
SP  - 161
EP  - 166
VL  - 22
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DMGAA_2002_22_2_a5/
LA  - en
ID  - DMGAA_2002_22_2_a5
ER  -