Related Clues:
- Collier's, for one: Abbr.
- 20-vol. reference work
- U.K. ref. bk.
- Brit. ref. bk.
- Brit. reference set
- In an env.
- Britannica, for one: Abbr.
- U.K. lexicon
- Its first vol. was published in 1884
- Bus. letter extra
- SASE, perhaps
- Brit. word reference
- Monument of lexicography, for short
- Oft-cited ref. book
- U.K. reference book