Standard measurements of birds
Anton Reichenow
<p><a rel="nofollow" class="external free" href="https://archive.org/stream/dievgelhandbuc01reic#page/65/mode/1up">https://archive.org/stream/dievgelhandbuc01reic#page/65/mode/1up</a>
</p>
Die Vogel : Handbuch der Systematischen Ornithologie. Volume 1