Related Clues:
- Letters to a mathematician
- Letters of proof
- Proof abbr
- Proof follow-up
- Where E is "erat"
- Letters seen by a proof reader?
- Math-proof letters
- Thus, in proofs
- End of many an argument
- Proof ending (Abbr.)
- Math text abbr.
- Letters at the end of a proof
- Argument-ending letters
- End-of-proof abbr.
- Logician's letters