engine can only display Latin-1 characters; non-Latin-1 Unicode

characters are displayed as "###".

Therefore, in the SGML files, we only use Latin-1 characters. We

typically encode these characters as HTML entities, e.g., Álvaro.

It is also possible to safely represent Latin-1 characters in UTF8

encoding for all output formats.

Therefore, in the SGML files, we can only use Latin-1 characters. We

can use UTF8 representations of Latin-1 characters, or HTML entities of

Latin-1 characters, e.g., Álvaro.

Do not use UTF numeric character escapes (&#nnn;).

When building the PDF docs, problem characters will appear as warnings.

HTML entities

official: http://www.w3.org/TR/html4/sgml/entities.html

one page: http://www.zipcon.net/~swhite/docs/computers/browsers/entities_page.html