1. Ministry of Aviation Technical Instruction No. 2.
2. Year Book, Tire & Rim Assoc. Inc., 1962. Section 7.
3. Runway Slipperiness and Slush. Walter B. Horne and Trafford J. W. Leland. Journal of the Royal Aeronautical Society, September 1963.
4. Av.P.970, Sec. 105 (Temperature Requirements). A.L.68, Fig. 1.