Physical Review LettersObservation and Saturation of a Multiphoton Process in Nd Cl3S. Singh, J. E. GeusicPublished Oct 17, 1966• 37 citationsPublisherAbstractReceived 15 September 1966DOI:https://doi.org/10.1103/PhysRevLett.17.865©1966 American Physical SocietyDOI10.1103/physrevlett.17.865