Asmus Freytag. <a href="http://www.unicode.org/unicode/reports/tr11/tr11-8.html"><cite>East Asian Width.</cite></a> 23 March 2001. Unicode Standard Annex #11. URL: <a href="http://www.unicode.org/unicode/reports/tr11/tr11-8.html">http://www.unicode.org/unicode/reports/tr11/tr11-8.html</a>