- Carboniferous (Wikipedia)
The Carboniferous (/ˌkɑːrbəˈnɪfərəs/ KAR-bə-NIF-ər-əs) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period 358.9 million years ago (mya), to the beginning of the Permian Period, 298.9 mya. In North America, the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian.
- Raven, volume 9-10 (2002–2003) (nava.org)
Raven 9/10, covering 2002 and 2003, appears as a special double issue, American City Flags. This milestone vexillological work contains 150 articles dedicated to descriptions and histories of municipal flags of the United States. The cities represented include the largest 100 cities in the country, at least two cities per state, and all state capitals.