TY - JOUR AU - Szymaniec, K AU - Chalupczak, W AU - Tiesinga, Eite AU - Williams, Carl AU - Weyers, S AU - Wynands, R. C2 - Physical Review Letters DA - 2007-04-13 00:04:00 LA - en M1 - 98 PB - Physical Review Letters PY - 2007 TI - Cancellation of the Collisional Frequency Shift in Caesium Fountain Clocks ER -