Dirac, P. A. M. (1942). “Bakerian Lecture. The Physical Interpretation of Quantum Mechanics”. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences180 (980): 1–39. Bibcode: 1942RSPSA.180....1D. doi:10.1098/rspa.1942.0023. JSTOR97777.
Ruzsa, Imre Z.; SzéKely, Gábor J. (1983). “Convolution quotients of nonnegative functions”. Monatshefte für Mathematik95 (3): 235–239. doi:10.1007/BF01352002.
Dirac, P. A. M. (1942). “Bakerian Lecture. The Physical Interpretation of Quantum Mechanics”. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences180 (980): 1–39. Bibcode: 1942RSPSA.180....1D. doi:10.1098/rspa.1942.0023. JSTOR97777.
Dirac, P. A. M. (1942). “Bakerian Lecture. The Physical Interpretation of Quantum Mechanics”. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences180 (980): 1–39. Bibcode: 1942RSPSA.180....1D. doi:10.1098/rspa.1942.0023. JSTOR97777.