Quartz clock

#	Item
51	PDF Document Add to Reading List Source URL: www.leapsecond.com Language: English - Date: 2005-01-26 14:37:02 Horology International Atomic Time Ephemeris time Atomic clock Universal Time Second Radio clock Quartz clock Caesium standard Measurement Clocks Time scales
52	PDF Document Add to Reading List Source URL: global.epson.com Language: English - Date: 2012-08-27 00:28:36 Seiko Time Watches Astron Quartz clock Tuning fork Marine chronometer Mechanical watch Quartz Horology Measurement Clocks