MBT-70 final design sketch.
US Army
R.P.Hunnicutt. <i>Abrams. A history of American main battle tank Vol.2</i>. — Presidio Press, 1990. <a href="//commons.wikimedia.org/wiki/Special:BookSources/0-89141-388-X" title="Special:BookSources/0-89141-388-X">ISBN 0-89141-388-X</a>