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<ext-link> External Link

Link to an external file or resource.

Usage/Remarks

Use the standard XLink attributes to provide a live link to the external source.
The @ext-link-type attribute can be used to give an indication of the type of resource to which the external link points. While this Tag Set does not constrain the values of this attribute, and ordinary text is acceptable, the suggested values include:
ec
Enzyme nomenclature. See http://www.chem.qmw.ac.uk/iubmb/enzyme/
gen
GenBank identifier
genpept
Translated protein-encoding sequence database
highwire
HighWire Press intrajournal
pdb
Protein data bank. See http://www.rcsb.org/pdb/
pgr
Plant gene register. See http://www.ebi.ac.uk/~textman/pgr-htdocs/pgr/
pir
Protein Information Resource. See http://pir.georgetown.edu
pirdb
Protein Information Resource. See http://pir.georgetown.edu
pmcid
PubMed Central identifier
pmid
PubMed identifier
sprot
Swiss-Prot. See http://www.ebi.ac.uk/swissprot/
aoi
Astronomical Object Identifier
doi
Digital Object Identifier
ftp
File transfer protocol
uri
Website or web service
Related Elements
<self-uri> is used when a book or book component is available in multiple forms, for example, as a means of indicating the online version of a print book or book part. Conversely, a URI that indicates a journal article, a companion book, or any other kind of external reference is usually tagged with <ext-link>. <uri>, although allowed everywhere <ext-link> is used, is more typically part of an address, information concerning a contributor, or part of a reference citation. Loosely put,
  • an external link element (<ext-link>) is intended to act as a link;
  • a URI element (<uri>) identifies a URI (such as a URL) in the text, but may or may not be a traversable link; and
  • a <self-uri> points to another form of the same book or book part (such as the PDF version of an online HTML eBook).
The address element <email> is allowed as part of a paragraph as well as inside an address. There are two ways to treat an email address in text: as an <email> element or as an <ext-link> element. If both a textual phrase (“the Moody Institute’s email address”) and a mailto URL are required, the <ext-link> element should be used.
The elements used in an address may include the address class elements: <addr-line>, <city>, <country>, <fax>, <institution>, <institution-wrap>, <state>, <phone>, and <postal-code> and the address linking class elements: <email>, <ext-link>, and <uri>.
Attributes
assigning-authority
ext-link-type
hreflang
specific-use

Base Attributes

id
xml:base
xml:lang

Linking Attributes

xlink:actuate
xlink:href
xlink:role
xlink:show
xlink:title
xlink:type

Namespaces

xmlns:xlink
Models and Context
May be contained in
<abbrev>, <address>, <addr-line>, <aff>, <alt-title>, <anonymous>, <array>, <article-title>, <attrib>, <award-id>, <bold>, <book-title>, <book-volume-id>, <book-volume-number>, <chapter-title>, <chem-struct>, <chem-struct-wrap>, <code>, <collab>, <comment>, <compound-kwd-part>, <conf-acronym>, <conf-loc>, <conf-name>, <conf-num>, <conf-sponsor>, <conf-theme>, <contrib>, <contrib-group>, <copyright-statement>, <corresp>, <data-title>, <def-head>, <degrees>, <disp-formula>, <disp-formula-group>, <edition>, <element-citation>, <email>, <etal>, <event-desc>, <ext-link>, <fax>, <fig>, <fig-group>, <fixed-case>, <funding-source>, <funding-statement>, <given-names>, <gov>, <graphic>, <index-entry>, <inline-formula>, <inline-media>, <inline-supplementary-material>, <institution>, <issue>, <issue-part>, <issue-title>, <italic>, <kwd>, <label>, <license-p>, <media>, <meta-name>, <meta-value>, <mixed-citation>, <monospace>, <name-address-wrap>, <named-content>, <nav-pointer>, <on-behalf-of>, <overline>, <p>, <part-title>, <patent>, <phone>, <prefix>, <preformat>, <product>, <publisher-loc>, <publisher-name>, <rb>, <related-article>, <related-object>, <role>, <roman>, <sans-serif>, <sc>, <see>, <see-also>, <see-also-entry>, <see-entry>, <self-uri>, <series>, <serif>, <sig>, <sig-block>, <source>, <speaker>, <std-organization>, <strike>, <string-conf>, <string-date>, <string-name>, <styled-content>, <sub>, <subject>, <subtitle>, <suffix>, <sup>, <supplement>, <supplementary-material>, <support-source>, <surname>, <table-wrap>, <table-wrap-group>, <target>, <td>, <term>, <term-head>, <th>, <title>, <toc-div>, <toc-entry>, <trans-source>, <trans-subtitle>, <trans-title>, <underline>, <unstructured-kwd-group>, <uri>, <verse-line>, <version>, <volume>, <volume-id>, <volume-series>, <volume-title>, <xref>
Description
Any combination of:
Content Model
<!ELEMENT  ext-link     (#PCDATA %ext-link-elements;)*               >
Expanded Content Model

(#PCDATA | email | ext-link | uri | inline-supplementary-material | related-article | related-object | hr | bold | fixed-case | italic | monospace | overline | overline-start | overline-end | roman | sans-serif | sc | serif | strike | underline | underline-start | underline-end | ruby | alternatives | inline-graphic | inline-media | private-char | chem-struct | inline-formula | tex-math | mml:math | abbrev | index-term | index-term-range-end | milestone-end | milestone-start | named-content | styled-content | fn | target | xref | sub | sup | x)*

Tagged Samples
Empty link
Display content must be generated
...
<p>... The highest 16S rDNA sequence similarity  
 value of 98&#x0025; was obtained for the 
 <italic>D. maris</italic> 16S rDNA sequence 
 (GenBank accession no. <ext-link ext-link-type="gen"
 xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="Y18883"/>)
 and for the <italic>D. maris</italic> DSM 43672<sup>T</sup>
 16S rDNA sequence (GenBank accession no. <ext-link
 ext-link-type="gen" xmlns:xlink="http://www.w3.org/1999/xlink"
 xlink:href="X79290"/>) ...</p>
...
Link with display content same as link 
...
<fig id="f1" orientation="portrait" position="float">
 <label>FIG. 1.</label>
 <caption>
  <p>(a) Schematic of the working principles of HFM, (b) a typical application
   scheme for an electric bias in HFM, (c) regulation the conformations and
   dynamics (trapping, concentration, and sudden stretching) of λ-DNA molecules
   in HFM, and (d) schematic of the trapping location regulation (enhanced online).
   [URL: <ext-link ext-link-type="uri" xlink:href="http://dx.doi.org/10.1063/1.4762852.1">
   http://dx.doi.org/10.1063/1.4762852.1</ext-link>]
   <alternatives>
    <media id="v1" mime-subtype="avi" mimetype="video" orientation="portrait"
      position="anchor" specific-use="original-format" xlink:href="v1"/>
    <media mime-subtype="mpeg" mimetype="video" orientation="portrait"
      position="anchor" specific-use="archival-format" xlink:href="v1"/>
    <media mime-subtype="x-flv" mimetype="video" orientation="portrait"
      position="anchor" specific-use="online-format" xlink:href="v1"/>
   </alternatives>
  </p>
 </caption>
 <graphic xlink:href="f1"/>
 <graphic id="f1a"  xlink:href="dummy1.png"/>
 <graphic id="f1b"  xlink:href="dummy2.png"/>
 <graphic id="f1c"  xlink:href="dummy3.png"/>
 <graphic id="f1d"  xlink:href="dummy4.png"/>
</fig>
...
Link with textual display content 
...
<p>In the mid-1990s, the GenBank database became part of the 
 International Nucleotide Sequence Database Collaboration with 
 the EMBL database (<ext-link xmlns:xlink="http://www.w3.org/1999/xlink"
 ext-link-type="uri" xlink:href="http://www.ebi.ac.uk/">European
 Bioinformatics Institute</ext-link>, Hinxton, United Kingdom) 
 and the Genome Sequence Database (GSDB; LANL, Los Alamos, NM).
 Subsequently, the GSDB was removed from the Collaboration (by
 the National Center for Genome Resources, Santa Fe, NM), and
 <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" 
 xlink:href="http://www.ddbj.nig.ac.jp/">DDBJ</ext-link> (Mishima, 
 Japan) joined the group. ...</p>
...
Email link 
...
<contrib-group>
 <contrib contrib-type="author">
  <name name-style="western">
   <surname>Nüsslin</surname>
   <given-names>Fridtjof</given-names>
   <prefix>Dr.</prefix>
  </name>
 </contrib>
 <aff>Klinik für Strahlentherapie und Radiologische Onkologie,
  <institution>Technische Universität München</institution>, 
  Munich, Germany (Tel: 49-89-41404517, E-mail:
  <ext-link ext-link-type="email" xlink:href="mailto:nuesslin@lrz.tum.de">
  nuesslin@lrz.tum.de</ext-link>)</aff>
</contrib-group>
...
DOI (with @assigning-authority) 
...
<p>In <italic>Developing Thin Clients Using Amphibious Epistemologies</italic> 
 (<ext-link ext-link-type="doi" xlink:href="http://dx.doi.org/10.5555/12345679" 
 assigning-authority="crossref">http://dx.doi.org/10.5555/12345679</ext-link>), 
 Josiah Carberry introduced &ldquo;Entrust,&rdquo; a linear-time tool for 
 simulating architecture.</p>  
...