<mime-type type="model/e57">
    <_comment>3d imaging data exchange</_comment>
    <magic priority="60">
      <match value="ASTM-E57" type="string" offset="0"/>
    </magic>
    <glob pattern="*.e57"/>
  </mime-type>
  <mime-type type="model/example"/>
  <mime-type type="model/iges">
    <_comment>Initial Graphics Exchange Specification Format</_comment>
    <glob pattern="*.igs"/>

can contain references.
</p>

<p>
When multiple values share underlying data, changing one value may change another.
For instance, changing an element of a <a href="#Slice_types">slice</a> will change
that element in the underlying array for all slices that share the array.
</p>

<h3 id="Underlying_types">Underlying types</h3>

<p>