« Status - June 2014 », sur WSDOT (consulté le ) : « WSDOT’s project team will now advance design work and expects construction to begin in 2015 and open the new route to service in 2017 »
wikipedia.org
en.wikipedia.org
The official guide of the Railways and Steam Navigation Lines of the U.S., Rand McNally & Company, May 1966. The guide shows that the service was operated jointly, some trains using Seattle's King Street Station and the rest Seattle's Union Station.
worldcat.org
Bruce Goldberg, Amtrak--the first decade, Silver Spring, MD, Alan Books, , 16–17 p. (OCLC7925036)