1. Accidents at blackspots: estimating the effectiveness of remedial treatment, with special reference to the ‘regression-to-mean’ effect;Abbess;Traffic Engineering and Control,1981
2. Evaluation of safety impact of highway projects;Al-Masaeid;Transportation Research Record,1993
3. Selection process for local highway safety projects;Barbaresso;Transportation Research Record,1982
4. Manual of Traffic Engineering Studies;Box,1976
5. Experimental and quasi-experimental designs for research on teaching;Campbell,1963