Tünnermann, H., Pöld, J. H., Neumann, J., Kracht, D., Willke, B., & Weßels, P. (2011). Beam quality and noise properties of coherently combined ytterbium doped single frequency fiber amplifiers. Optics Express, 19(20), 19600-19606. doi:10.1364/OE.19.019600.