vendor/symfony/css-selector/Tests/XPath/Fixtures/lang.xml

<test>
  <a id="first" xml:lang="en">a</a>
  <b id="second" xml:lang="en-US">b</b>
  <c id="third" xml:lang="en-Nz">c</c>
  <d id="fourth" xml:lang="En-us">d</d>
  <e id="fifth" xml:lang="fr">e</e>
  <f id="sixth" xml:lang="ru">f</f>
  <g id="seventh" xml:lang="de">
    <h id="eighth" xml:lang="zh"/>
  </g>
</test>