6.
P.J. Ruckel, S.M. Acott, R.H. Bowering, Foamed-Asphalt Paving Mixtures: Preparation of Design Mixes and Treatment of Test Specimens. In: Asphalt materials, mixtures, construction, moisture effects and sulfur, Washington, DC: TRB – Transportation Research Board, 1982, 911, National Research Council USA, p. 88-95.