1. WOOD , R. W. 1934. Physical Optics, third edition, 182–184. 300NewYork: The Macmillan Company.
2. BORN , M. and
WOLF , E. 1980. Principles of Optics, sixth edition, 270–271. Oxford: Pergamon Press.
3. KAYE , G. W. C. and
LABY , T. H. 1960. Physical and Chemical Constants, twelfth edition, 79London: Longmans.