B. Dannecker, M. Abdou Ahmed, and T. Graf. 7th EPS-QEOD EUROPHOTON CONFERENCE "Solid State, Fibre, and Waveguide Coherent Light Sources" , 7, page SSL-5.1. European Physical Society (EPS), European Physical Society (EPS), (2016)
F. Fetzer, H. Hu, P. Berger, R. Weber, and T. Graf. High-Power Laser Materials Processing: Applications, Diagnostics, and Systems VII, volume 10525 of Proc. SPIE, SPIE, (February 2018)