1. EMPIR project “Reference algorithms and metrology on aspherical and freeform optical lenses”, www.ptb.de/empir/freeform-home.html.
2. CC UPOB, 2016 Workshop Asphere Metrology, http://upob.de/index.php?option=com_phocadownload&view=category&id=23:cc-upob-workshops&Itemid=70
3. EMRP project “Optical and tactile metrology for absolute form characterization”, http://www.ptb.de/emrp/ind10.html.
4. Interferometer for precise and flexible asphere testing
5. Calibration of a non-null test interferometer for the measurement of aspheres and free-form surfaces