The mathematical theory of Huygens' principle, by Bevan B. Baker and E.T. Copson. Baker, Bevan B. (Bevan Braithwaite), 1890- Copson, E. T. (Edward Thomas), 1901- joint author. Wave theory of light. Diffraction. QC403 .B3 1950 510 BAM Bibliographical footnotes. Oxford, Clarendon Press, 1950. 1950. 1950 Text vi, 192 p. eng