TY  - RPRT
TI  - NIST time and frequency bulletin, no. 554 
AU  - Petty, Eyvon M
PY  - 2004
PB  - National Institute of Standards and Technology
CY  - Gaithersburg, MD
SN  - NIST IR 6630-02
DO  - 10.6028/NIST.IR.6630-02
ER  -