@misc{bsel2018double,
  title={Double freeform illumination design for prescribed wavefronts and irradiances},
  author={Christoph Bösel and Herbert Gross},
  year={2018},
  eprint={1801.07479},
  archivePrefix={arXiv},
  primaryClass={physics.optics},
  doi={10.1364/JOSAA.35.000236},
  url={https://arxiv.org/abs/1801.07479}
}