The content model for the <etal> element
Many journal Tag Sets model the <etal> element as EMPTY, that is, the element has no content. Such an empty element is typically used as a place holder, for example, to generate the text “et al.” via a stylesheet. In this Tag Set, the element is usually used as an empty element, but the Tag Set also accommodates those journal Tag Sets that expect content inside <etal>, so the element is modeled with text content instead of as formally EMPTY and may contain text such as “Associates, co-workers, and colleagues”.
<!ENTITY % etal-model "(#PCDATA %etal-elements;)*" >