Hart, Daniel, Thomas M. Donnelly, and James Youniss (2007), "High School Community Service as a Predictor of Adult Voting and Volunteering", American Educational Research Journal, 44, 197-219.
- Civic knowledge includes information on government functioning, current political issues, and community needs. It was indexed by a standardized test consist- ing of citizenship(federal government, citizen rights and responsibilities), American history (political and economic), and geographic (patterns of food production and settlement across societies)questions.
- Rock, D.A., J.M. Pollack, and P. Quinn (1995) , "Psychometric report for the NELS:88 base year through second follow-up.".