TY - GEN AU - Petrina C. Potts C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 2013-07-01 04:07:00 DO - https://doi.org/10.6028/NIST.IR.1149-07 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 2013 TI - NIST time and frequency bulletin: ER -