Frondel, M., & Schmidt, C. M. (2001). Do environmental programs really work?: The perspective of modern evaluation research. Discussion paper series.
Chicago-Zitierstil (17. Ausg.)Frondel, Manuel, und Christoph M. Schmidt. "Do Environmental Programs Really Work?: The Perspective of Modern Evaluation Research." Discussion Paper Series 2001.
MLA-Zitierstil (9. Ausg.)Frondel, Manuel, und Christoph M. Schmidt. "Do Environmental Programs Really Work?: The Perspective of Modern Evaluation Research." Discussion Paper Series, 2001.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.