They may appear in any order. Attribute names are always case-insensitive.
Attribute values are generally case-insensitive.
Multiple destinations are given delimited by commas. ALL - Style information should be used for rendering to all devices. It may also be used to identify the Style Sheet in order to allow the user to have control over turning it on or off. An alphanumeric string. In addition to the specific attributes above, there are more generic attributes which have been organized into three separate categories.