Laser locking to the 'ANTPOT. 199 HG' 'ANTPOT. 1 So' - 'ANTPOT. 3 Po' clock transition with 5.4 x '10 POT.-15'/''tau' POT.1/2' fractional frequency instability - McFerran, John J.; Magalhães, Daniel Varela; Mandache, C.; Millo, J.; Zhang, W.; Le Coq, Y.; Santarelli, G.; Bize, Sebastien (Optics Letters, 2012)