RT Book, Section SR 00 ID 10.1007/BFb0115047 A1 Khapalov, A. Yu. T1 Observability of hyperbolic systems with interior moving sensors YR 1993 FD 1993 VO 185 SP 489 OP 499 T2 Analysis and Optimization of Systems: State and Frequency Domain Approaches for Infinite-Dimensional Systems PB Springer Berlin Heidelberg PP Germany T3 Lecture Notes in Control and Information Sciences SN 978-3-540-47480-7 AV Published LK https://pure.iiasa.ac.at/id/eprint/14163/