Dirac,  P.A.M.  "Quantum Theory of Localizable Dynamic Systems",   American Physical Society,  in the Physical Review, 73/9, 1 May 1948.  Original printed wrappers. Very good condition.  This is one of only eight (total)  articles published by Dirac in an APS-sponsored publication (see bottom).  $500

_____.  Another copy, though this one has a very small (1/4-inch) chip missing at the upper left corner of the front wrapper).  $350

OTHER PAPERS in this issue include: Excitation Function for Proton-Neutron Reaction in Lithium Li7(p,n) J. E. Hill and W. E. Shoupp pp. 931-933 Note on Second Born Approximation and Proton-Neutron and Proton-Proton Scattering Ta-You Wu Nuclear Properties of 93237 Arthur C. Wahl and Glenn T. Seaborg pp. 940-941 Shapes of Nuclear Induction Signals Boris A. Jacobsohn and Roald K. Wangsness pp. 942-946 A Photographic Study of the Neutron Spectra from Al(αn) and Si(dn) R. A. Peck pp. 947-955 Search for a Resonance Absorption of Neutrons in Graphite S. Bernstein pp. 956-962 Slow Neutron Velocity Spectrometer Studies of Cu, Ni, Bi, Fe, Sn, and Calcite W. W. Havens, L. J. Rainwater, C. S. Wu, and J. R. Dunning pp. 963-972 Neutron-Proton and Proton-Proton Scattering at High Energies Julius Ashkin and Ta-You Wu pp. 973-985 Elastic and Inelastic Scattering of 100- to 200-Mev Protons or Neutrons by Deuterons Ta-YOU Wu and Julius Ashkin pp. 986-1001 On the Behavior of Cross Sections Near Thresholds Eugene P. Wigner pp. 1002-1009 The Production of Nucleons by the Cosmic Radiation. II. S. A. Korff and A. Cobas pp. 1010-1014 Gamma-Rays from Alpha-Particle Reactions David E. Alburger pp. 1014-1019 A Note on Saturation in Microwave Spectroscopy Robert Karplus and Julian Schwinger pp. 1020-1026 Frequency Modulation in Microwave Spectroscopy Robert Karplus pp. 1027-1034 Radioactive Cerium and Praseodymium M. L. Pool and N. L. Krisberg pp. 1035-1041 Trajectories of Charged Meson Test Particles in the Similarity Geometry Banesh Hoffmann pp. 1042-1046 The Breakdown of Gases in High Frequency Electrical Fields Donald H. Hale pp. 1046-1052 Saturation Effect in Microwave Absorption of Ammonia Robert L. Carter and William V. Smith pp. 1053-1058 Secondary Electron Emission from Targets of Barium-Strontium Oxide J. B. Johnson pp. 1058-1073 Mechanical Properties of Long Chain Molecule Liquids at Ultrasonic Frequencies W. P. Mason, W. O. Baker, H. J. Mcskimin, and J. H. Heiss pp. 1074-1091 Quantum Theory of Localizable Dynamical Systems P. A. Dirac pp. 1092-1103 Crystal Radii of the Heavy Elements W. H. Zachariasen pp. 1104-1105 The Question of Non-Singular Solutions in the Generalized Theory of Gravitation A. Papapetrou pp. 1105-1108 On the Hyperfine Structure of Deuterium Aage Bohr pp. 1109-1111 Abstract from AIP's great PROLA website: "A dynamical system is called localizable if its wave functions can be expressed in terms of variables, each referring to physical conditions at only one point in space-time. These variables may be at points on any three-dimensional space-like surface in space-time. A general investigation is made of how the wave function varies when the surface is varied in any way. The variation of the wave function is given by equations of the Schrödinger type involving certain operators Hn(u) which play the role of Hamiltonians. The commutation relations for these operators are obtained (Eqs. (50), (51)). The theory works entirely with relativistic concepts and it provides the general pattern which any relativistic quantum theory must conform to, provided the dynamical system is localizable .