1. Performance-based track-quality measures and their application to maintenance-of-way planning;Corbin;Transp Res Rec: J Transp Res Board,1981
2. Track-quality indices and track-degradation models for maintenance-of-way planning;Hamid;Transp Res Rec: J Transp Res Board,1981
3. Development of railroad track degradation models;Bing;Transp Res Rec: J Transp Res Board,1983
4. Analytical descriptions of track-geometry variations;Hamid;Transp Res Rec: J Transp Res Board,1981
5. Esveld C. Modern Railway Track. 2nd ed., 2001. isbn:90-8004-324-3-3.