@misc{1203671, author = {Gwen E Bennett}, title = {NIST time and frequency bulletin, no.520:}, year = {2001}, month = {2001-01-01 05:01:00}, publisher = {, National Institute of Standards and Technology, Gaithersburg, MD}, doi = {https://doi.org/10.6028/NIST.IR.6604-03}, language = {en}, }