Lücking, F., Assion, A., Apolonskiy, A., Krausz, F., & Steinmeyer, G. (2012). Long-term carrier-envelope-phase-stable few-cycle pulses by use of the feed-forward method. Optics Letters, 37(11), 2076-2078. doi:http://dx.doi.org/10.1364/OL.37.002076.