TY - GEN AU - Bennett, Gwen E C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1997-01-01 05:01:00 DO - https://doi.org/10.6028/NIST.IR.5057-12 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1997 TI - NIST time and frequency bulletin no. 481: ER -