Content model for a full (complex) journal article which may contain sub-articles and/or
responses to the article in addition to the text in the article’s front, body, and back matter
The <floats-group> element used in this article model is a container element to hold the floating objects (figures, tables, text boxes, graphics,
etc.) that occur anywhere in the article proper (not within a sub-article or response, each of which is modeled to contain
its own <floats-group>), where such floating objects are collected together rather than interspersed throughout the article narrative where they
are referenced. This element was added to accommodate publishers who like to group all such floating objects together, at
the end of an article.