Any image that has a "longdesc" attribute must also have a corresponding "d-link," or Description link. This should point to the same resource as the "longdesc" attribute and should only contain the text "d".

Example

Wrong

<img src="complexImage.png" alt="A complex image that cannot be described succinctly." longdesc="longer_description.html">

Right

<img src="complexImage.png" alt="A complex image that cannot be described succinctly." longdesc="longer_description.html"><a href="longer_description.html">d</a>