"Dirac was one of the greatest theoretical physicists in the twentieth century. He is best known for his important and elegant contributions to the formulation of quantum mechanics; for his quantum theory of the emission and absorption of radiation, which inaugurated quantum electrodynamics...Present expositions of quantum mechanics largely rely on his masterpiece The Principles of Quantum Mechanics" (D.S.B.). Dirac received the Nobel prize for physics in 1933 together with Schrodinger "for the discovery of new fruitful forms of atomic theory". With the ownership signature of physicist David R. Inglis on front pastedown.