rbeezer
commented
7 years ago RELAX-NG Schema now says a preface can contain
Content: title?, idx*, (((p | blockquote | pre | todo | sidebyside)+, attribution*) | contributors)which is basically paragraphs, an attribution, with "illustrations" in a sidebyside. No numbered items here. But maybe a restricted version of paragraphs would be useful as a lightweight division?
See https://groups.google.com/forum/#!topic/mathbook-xml-support/6UKwlthV_Dk Same for dedication, etc. in front matter.