1. Optical Shop Testing
2. Zygo Inc., “Laser Interferometers”, https://www.zygo.com/?/met/interferometers/ (2017)
3. Trioptics, “Wavefront and surface measurements with interferometers and shack hartmann sensors”, http://www.trioptics.com/knowledge-base/wavefront-and-surface-measurement/ (2017)
4. Metrology, mirrors and gratings – advances an challenges in synchrotron optics;Siewert,2013
5. Optical measurement of absolute flatness with a deflectometric measurement system at PTB;Ehret,2013