1. ‘Everything You Always Wanted to Know about the IRI, But Were Afraid to Ask!' Road Profile Users Group Meeting September 22–24;Gillespie,1992
2. Sayers, M., Gillespie, T. and Queiroz, C. 'The International Road Roughness Experiment', World Bank, Washington DC, Technical Paper No. 45, 1986.
3. 'On calculation of International Roughness Index from longitudinal Road Profiles', Pavement–vehicle interaction and Traffic Monitoring;Sayers;Transportation Research Record,1995
4. Two quarter-car models for defining road roughness: IRI and HRI;Sayers;Transportation Research Record,1989
5. Full-car roughness index as summary roughness statistic;Capuruco;Journal of the Transportation Research Board,1905