"Olson Database", available for download from ftp://elsie.nci.nih.gov/pub/
These comments were included in each file.
# This file is in the public domain, so clarified as of
# 2009-05-17 by Arthur David Olson.
# This data is by no means authoritative; if you think you know better,
# go ahead and edit the file (and please send any changes to
# tz@elsie.nci.nih.gov for general use in the future).