External module in the base Suite that declares the bibliographic reference elements, i.e., those elements that may appear inside a <citation> element. The element <nlm-citation> uses many of the same elements, but in a specified sequence.
<!ENTITY % references.ent PUBLIC "-//NLM//DTD Archiving and Interchange DTD Suite Bibliographic Reference (Citation) Class Elements v2.3 20070202//EN" "references.ent" >
modules.ent