TY  - JOUR
AU  - Giovanni Dore
AU  - Alberto Venni
TI  - On the Closedness of the Sum of Two Closed Operators.
JO  - Mathematische Zeitschrift
PY  - 1987
SP  - 189
EP  - 202
VL  - 196
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MZ_1987__196_173874/
ID  - MZ_1987__196_173874
ER  -