@misc{1200281, author = {Kathryn Stephenson}, title = {NIST time and frequency bulletin:}, year = {2019}, month = {2019-09-01 04:09:00}, publisher = {, National Institute of Standards and Technology, Gaithersburg, MD}, doi = {https://doi.org/10.6028/NIST.IR.8261-07}, language = {en}, }