The following XPath expression selects the <placetype> element no matter
where it appears in the XML document:

//*[placetype]

//*[rpid:placetype]

http://www.schemavalid.com/faq/xml-schema.html

http://www.jabber.org/jeps/jep-0108.html


GML
http://www.gmlcentral.com/


Import XML
http://www.posc.org/ebiz/Guidelines/ImportingModules.html
http://www.xfront.com/VariableContentContainers.html

http://www.xfront.com/ZeroOneOrManyNamespaces.html

http://www.jdrosen.net/papers/draft-ietf-simple-presence-data-model-02.txt


RELAX NG

http://www.relaxng.org/
http://www.relaxng.org/tutorial-20011203.html

https://www.sipfoundry.org/cgi-bin/user_manage

https://scm.sipfoundry.org/rep/ietf-drafts/simple/schemas/


http://www.w3.org/2001/03/webdata/xsv
http://tools.decisionsoft.com/schemaValidate.html
http://apps.gotdotnet.com/xmltools/xsdvalidator/ 


---

<xs:any "##local" processContents="skip"/>
<xs:any "##other" processContents="lax"/>


----

<new-activity specializes="meal">dejeuner</new-activity>

http://www.xml.com/lpt/a/2004/10/27/extend.html