1. Rupp, D. T., Beemer, J.D., Swindern, L.R.; High Platform II Final Report, August 14, 1970; Raven Industries, Inc. (BT-2150)
2. Munson,JamesB.;DesignandManufactureofa 670,000 Cubic Foot Natural ShapeBalloon for Project POBAL; September 15, 1972; G.T. Schjeldahl Co. (BT-1204)