@misc{1203446, author = {Eyvon M Petty}, title = {NIST time and frequency bulletin, no. 560:}, year = {2004}, month = {2004-01-01 05:01:00}, publisher = {, National Institute of Standards and Technology, Gaithersburg, MD}, doi = {https://doi.org/10.6028/NIST.IR.6630-08}, language = {en}, }