The HTML incantation is <SPAN style="FONT-FAMILY: Gentium Alt">u̯</SPAN>, which yields u̯. If this looks like u followed by a box on your browser, that's because
- You don't have the Gentium Alt font installed on your computer. I downloaded the font for free from http://www.fontica.com/font/gentium_alt and unzipped it into the fonts folder on my computer.
- You haven't instructed your web browser to render pages using the Gentium Alt font.
- Even if you instructed your web browser to render pages using the Gentium Alt font, it doesn't follow your instructions properly. I find that Internet Explorer doesn't render the inverted breve below the letter u correctly, but Google Chrome does.