@conference{122596, author = {Steven Jefferts and Thomas Heavner and Jon Shirley and Thomas Parker}, title = {Systematic Frequency Shifts and Quantum Projection Noise in NIST-F1}, year = {2001}, month = {2001-01-01}, publisher = {6^uth^ Symposium on Frequency Standards and Metrology , St. Andrews, SC}, language = {en}, }