TY  - GEN
AU  - Bonsall, F. F
AU  - Duncan, J
TI  - Numerical Ranges of Operators on Normed Spaces and of Elements of Normed Algebras
SN  - 521079888
PY  - 1971///
CY  - Cambridge
PB  - Cambridge. At the University Press
N1  - Contine bibliografie si index
ER  -