London: Published for The Royal Society by Harrison & Sons, 1925.
First edition of Paul Dirac's first major paper, as published in Proceedings of the Royal Society of London, Series A, Vol. 109, Dirac's paper pp. 642-653; total pages 561-653, plus obituary notices of Fellows (I-XXXIV). In publisher's original wrappers, with new spine, pages toned and with creasing to bottoms, stamp to blank verso of plates. Very Good. Item #140940039