Time zone data source information

Primary source:

Background sources and references:

• H. M. Nautical Almanac Office, United States Naval Observatory. "World Time Zone Map." Astronomical Applications Department. »
• National Atlas of the United States, United States Geological Survey. "Time Zones of the United States." nationalatlas.gov. »
• Time and Date AS. "Time Zone and Other Travel Tools." time and date.com. »
• Twin Sun, Inc. Sources for Time Zone and Daylight Saving Time Data. »
• WorldTimeZone.com. WorldTimeZone. »