1. F.H. Smith, Interference microscope, US Patent 2601175, (5 August 1947).
2. Microscopic interferometry;Smith;Research (London),1955
3. Polarization interferometer and its applications;Lebedeff;Rev. Opt.,1930
4. G. Nomarski, Interferential polarizing device for study of phase object, US Patent 2924142 (14 May 1952).
5. The Zeiss–Nomarski differential equipment for transmitted light microscopy;Allen;Zeitschrift für Wissenschaftliche Mikroscopie und Mickroskopische Technik,1969