| Answer | Crossword Clue |
|---|---|
| ERA | History book topic |
| ERA | History topic |
| ERA | History text topic |
| ERA | History class topic |
| ORGANIZEDLABOR | History-of-socialism lecture topic: ORAL-B |
| ESSAY | Blue book topic |
| USAGE | Grammar book topic |
| UFOS | Topic of the USAF's Project Blue Book |
