- Terrestrial Ecoregions of North America: A Conservation Assessment (World Wildlife Fund Ecoregion Assessments)
- Freshwater Ecoregions of North America: A Conservation Assessment (World Wildlife Fund Ecoregion Assessments)
- Democratic Legislative Institutions: A Comparative View: A Comparative View
- The legislative process: A comparative approach
- A Conservation Assessment of the Terrestrial Ecoregions of Latin America and the Caribbean