1. AAHSTO (American Society of State Highway and Transportation Officials) 1986. Guide for the design of pavement structures.
2. Barber, E.S. & Sawyer, C.L., 1952. Highway sub-drainage HRB Proc. Vol 31 p642–666.
3. Biczysko, S.J. 1985. Permeable sub-bases in highway construction. Proc. 2nd Symp. on Unbound Aggregates in Roads (UNBAR2). Ed. Jones R.H., Dept. of Civ. Eng. University of Nottingham p81–92.
4. Base course drainage for airport pavements;Casagrande;ASCE Trans,1952
5. Drainage of Highway and Airfield Pavements;Cedergren,1974