Values for the ref-type attribute. These values name the type of element to which an internal reference is pointing, for example, “fig” for a reference to a <fig>.
The values may be used to control type-specific processing or validation.
<!ENTITY % ref-types "aff | app | author-notes | bibr | boxed-text | chem | contrib | corresp | disp-formula | fig | fn | kwd | list | plate | scheme | sec | statement | supplementary-material | table | table-fn | other" >
link.ent