1. Design for railroad ballast and sub grade support;Raymond;J Geotech Eng Div,1978
2. Causes of fouling in track;Selig;Area Bull,1988
3. Collingwood BI. An investigation of the cause of railroad ballast fouling. Master of Science Degree Project Report No. AAR88-350P. University of Massachusetts; 1988.
4. Selig ET, DelloRusso V, Laine KJ. Sources and causes of ballast fouling. Report No. R-805. Association of American Railroad (AAR), Technical Center, Chicago; 1992.
5. CN (Canadian National) Rail. Ballast performance in concrete tie track. Prairie region. Edmonton. CN, Geotechnical Service. Internal report; 1987.