Version of the BITS Tag Set that should be used to validate this book or book part.
Best Practice: This attribute should be set on every document instance explicitly, even when using the XSD or RNG version of BITS. This is a “fixed” attribute (meaning that the value is set via a parameter entity in the DTD; thus, an author or editor cannot change it) that should change every time the BITS Tag Set changes version number.
| Value | Meaning |
|---|---|
| 1.0 | The version of the BITS Tag Set that is being used. |
| Restriction: | |