@misc{1203126, author = {Eyvon M Petty}, title = {NIST time and frequency bulletin, no. 618:}, year = {2009}, month = {2009-01-01 05:01:00}, publisher = {, National Institute of Standards and Technology, Gaithersburg, MD}, doi = {https://doi.org/10.6028/NIST.IR.6656-06}, language = {en}, }