TY  - GEN
AU  - 
AU  - 
ED  - United States.
TI  - Frequency standards and clocks : a tutorial introduction
T2  - NBS technical note
U1  - US 539.14 23rd ed.
PY  - 1977///
CY  - Washington
PB  - U.S. Department of Commerce
KW  - Atomic clocks
KW  - Atomic frequency standards
N1  - 2 nd revision
ER  -