TY  - BOOK
AU  - Freund E
TI  - Zeitvariable mehrgrobensysteme
T2  - Lecture notes in operstions research and mathemtaical sysems; 57
U1  - B2893P,1, 113L1 
PY  - 1971///
CY  - Berlin
PB  - Springer Verlag      
ER  -