Characters not supported in xml element

[Codeless]

Is there a difinitive list somewhere of characters that are not supported in xml elements? I have found some by trial and error such as "/", ",", and "&". But is there a list?

 

[hog]

According to my book element names can be any length and may contain letters, digits, underscores, hyphens and periods. They must begin with a letter or an underscore. XML is also case sensitive so <Myelement> is not the same as <myelement>