era: References & Edit History
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Article History
| Type | Description | Contributor | Date |
|---|---|---|---|
| Added geologic time chart. | Apr 11, 2018 | ||
| Noted that eras are the second-longest portions of geologic time and updated the boundary years that separate one era from another. | Apr 11, 2018 | ||
| Added geologic time boundary years. | May 25, 2010 | ||
| Article added to new online database. | Jul 20, 1998 |
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