Physical Review LettersComment on "Contractive States and the Standard Quantum Limit for Monitoring Free-Mass Positions"K. WódkiewiczPublished Feb 27, 1984• 11 citationsPublisherAbstractReceived 7 November 1983DOI:https://doi.org/10.1103/PhysRevLett.52.787©1984 American Physical SocietyDOI10.1103/physrevlett.52.787