et al. in biblioentry

["Imsieke, Gerrit, le-tex" <gerrit.imsieke@le-tex.de>]

It has been asked before [1,2], but I haven’t seen a useful 
recommendation yet for capturing “more authors” in a structured 
bibliographic entry, that is, an entry that does not permit untagged 
prose within.

I am tasked with marking up the following reference in DocBook 5.0:

[9] Tim Berners-Lee et al. Uniform Resource Identifier (URI): Generic 
Syntax. The Internet Society. https://www.ietf.org/rfc/rfc3986.txt

What I have so far:

<biblioentry xml:id="RFC3986" xreflabel="[9]">
  <authorgroup>
    <author>
      <personname>
        <firstname>Tim</firstname>
        <surname>Berners-Lee</surname>
      </personname>
    </author>
  </authorgroup>
  <title>Uniform Resource Identifier (URI): Generic Syntax</title>
  <publishername>The Internet Society</publishername>
  <biblioid class="uri">https://www.ietf.org/rfc/rfc3986.txt</biblioid>
</biblioentry>

What is missing in the markup: “et al.”.

Let’s assume that I don’t have a complete list of authors and I can’t 
find it out. Or that I’m unwilling to look them up and code them 
manually. Or that I’m an automatic converter that is not smart enough to 
look them up at the given URI. Or that there are just too many authors 
to type them all.

I can’t imagine that DocBook does not have an element like JATS’s etal [3]

[1] http://markmail.org/message/owvosoqcjxl6xzbd
[2] http://markmail.org/message/u3ij3ble7bmxz35c
[3] http://jats.nlm.nih.gov/archiving/tag-library/1.1/element/etal.html

Any recommendations? Am I missing something obvious?

Gerrit

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Gerrit Imsieke
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