 the default
          PDF fonts.
        </p>
<p>
          If you use your own fonts, the font must have a glyph for
          the desired character. Furthermore the font must be
          available on the machine where the PDF is viewed or it must
          have been embedded in the PDF file. See <a href="fonts.html">embedding fonts</a>.
        </p>
<p>
          For most symbols, it is better to select the symbol font
          explicitely, for example in order to get the symbol for the
          mathe