Corrigendum: Experimental realization of an optical second with strontium lattice clocks

Nature Communications 4: Article number: 2109 (2013); Published: 9 July 2013; Updated: 31 October 2013. In the legend to Fig. 4c in this Article, references 47 and 48 were incorrectly included in a list of sources for 87Sr clock frequency measurements. The correct sources are Hong et al.49 and Yamaguchi et al.