External module in the Book Tag Set (and Collection Tag Set) that names all Book-Tag-Set-specific Suite external modules to be used by the two DTDs. (Note: This module does not declare itself, either DTD, any of the base Suite modules, or the Suite Module of Modules which declares the base Suite modules.)
<!ENTITY % bookcustom-modules.ent PUBLIC "-//NLM//DTD Book DTD Module of Modules v3.0 20080202//EN" "bookcustom-modules3.ent" >
bookandcoll-for-taglib3.dtd