00823nam0-22002891i-450-990001034470403321000103447FED01000103447(Aleph)000103447FED0100010344720000920d1962----km-y0itay50------baengInvariance in Quantum Mechanics and Group Extensionsby Louis MichelBures-sur-YvetteIHES Saclay1962Report I.H.E.S.Teoria dei gruppiPrincipi di simmetria512Michel,Louis346876ITUNINARICAUNIMARCBK99000103447040332110A-0142873FI1FI1Invariance in Quantum Mechanics and Group Extensions339036UNINAING01