2013 US Senate investigation into Apple's offshore tax structure in Ireland, and Apple Sales International
US Senate (page 20)
<a rel="nofollow" class="external free" href="https://www.hsgac.senate.gov/imo/media/doc/EXHIBITS%201-19%20(May%2021%202013)3.pdf">https://www.hsgac.senate.gov/imo/media/doc/EXHIBITS%201-19%20(May%2021%202013)3.pdf</a>