Element class created to hold the <element-citation> and <mixed-citation> elements, which reference an external document, as used within, for example, the text of a paragraph
This class has been made intentionally small, so that the citation elements may be used in many places, but restricted overall.
<!ENTITY % citation.class "element-citation | mixed-citation | nlm-citation" >
JATS-archivecustom-classes0.ent