Affiliation: | Bureau International des Poids et Mesures, F-92312 Sèvres Cedex, France;National Institute of Standards and Technology, Gaithersburg, MD 20899 USA;National Institute of Standards and Technology, Gaithersburg, MD 20899 USA;Bureau International des Poids et Mesures, F-92312 Sèvres Cedex, France |