Physical Review LettersComment on "Contractive States and the Standard Quantum Limit for Monitoring Free-Mass Positions"Robert LynchPublished May 7, 1984• 16 citationsPublisherAbstractReceived 30 January 1984DOI:https://doi.org/10.1103/PhysRevLett.52.1729©1984 American Physical SocietyDOI10.1103/physrevlett.52.1729