<a href="https://en.wikipedia.org/wiki/Caerlaverock_Castle" class="extiw" title="en:Caerlaverock Castle">Caerlaverock Castle</a>, Scotland.
David MacGibbon and Thomas Ross
<i>The Castellated and Domestic Architecture of Scotland from the twelfth to the eighteenth centuries</i>, Vol. 1 (<a rel="nofollow" class="external text" href="https://archive.org/details/castellateddomes01macguoft">Read Online</a>).