Highly-efficient 1-GHz-repetition-frequency femtosecond Yb3+:KY(WO4)2 laser for super-continuum generationT.C. Schratwieser, C.G. Leburn and D.T. ReidEPJ Web of Conferences, 41 (2013) 10019DOI: https://doi.org/10.1051/epjconf/20134110019