My favorite title for a paper is "Dating events in the vicinity of a leap second: (pdf) <a href="http://tf.nist.gov/timefreq/general/pdf/1788.pdf" rel="nofollow">http://tf.nist.gov/timefreq/general/pdf/1788.pdf</a>.  And for more interesting detail, see <a href="http://www.nist.gov/index.html" rel="nofollow">http://www.nist.gov/index.html</a> searching for UT0 UT1 and UT2.<p>And for a bit of history, albeit somewhat painful, see <a href="http://naggum.no/lugm-time.html" rel="nofollow">http://naggum.no/lugm-time.html</a>.