TY  - BOOK
AU  - Jespersen James
TI  - From sundials to atomic clocks:  : understanding time and frequency
SN  - 0-486-40913-9
AV  - QB209.J52 1999 
PY  - 1999///
CY  - Mineola
PB  -  : inc Dover publications
KW  - Time
KW  -  Time measurements
KW  -  Clocks and watches
N1  - Includes bibliographical references and index
ER  -