TY  - DATA
AU  - Paul Leo Butzer; Hubert Berens
TI  - Semi-Groups of Operators and Approximation
SN  - 9783642460661
PY  - 1967///
PB  - Springer Berlin Heidelberg
KW  - Mathematics and Statistics
UR  - https://doi.org/10.1007/978-3-642-46066-1
ER  -