Sound Transit Board (July 28, 2011). "Sound Transit Motion No. M2011-51"(PDF). Sound Transit. Archived(PDF) from the original on December 22, 2015. Retrieved April 14, 2015.
Sound Transit Board (July 28, 2011). "Sound Transit Motion No. M2011-51"(PDF). Sound Transit. Archived(PDF) from the original on December 22, 2015. Retrieved April 14, 2015.