1. 23 CFR 490.105. National Performance Management Measures for the Assessing Pavement Condition. Code of Federal Regulations. https://www.ecfr.gov/current/title-23/chapter-I/subchapter-E/part-490/subpart-C.
2. 23 CFR 490.105. National Performance Management Measures for the Assessing Pavement Condition. Code of Federal Regulations. Establishment of Performance Targets. https://www.ecfr.gov/current/title-23/chapter-I/subchapter-E/part-490/subpart-A/section-490.105#p-490.105(e)(4)(iii)and(iv).
3. McGhee K. H. Development and Implementation of Pavement Condition Indices for the Virginia Department of Transportation, Phase 1, Flexible Pavements. September 2002. https://www.virginiadot.org/business/resources/LAD_Documents/Flexible_Pavements_Development_of_Pavement_Condition_Indices_Phase_I.pdf
4. Models Relating Pavement Quality Measures