Historical clue formulations

• Business letter abbr. — 2016-08-02
• Env. within an env., perhaps — 2013-03-19
• S.A.S.E., e.g.: Abbr. — 2012-12-05
• Abbr. on a business letter — 2012-08-23
• Check within, say?: Abbr. — 2012-07-28
• Abbr. on the bottom of a business letter — 2012-06-06
• Return envelope, e.g.: Abbr. — 2011-04-27
• Abbr. at the bottom of a letter — 2011-04-21
• Bottom-of-letter abbr. — 2010-12-28
• Letter abbr. — 2009-02-07
• Bottom-of-letter abbr. — 2007-09-02
• Bottom-of-letter abbr. — 2006-10-01
• Check inside?: Abbr. — 2006-09-23
• S.A.S.E., e.g.: Abbr. — 2006-08-01
• Letter accompanier: Abbr. — 2005-01-17
• Abbr. at the bottom of a business letter — 2004-05-25
• Abbr. at the bottom of a business letter — 2003-11-16
• S.A.S.E., e.g. — 2003-06-04
• Abbr. on a business letter — 2002-08-14
• Business letter abbr. — 2002-06-23
• Abbr. on a business letter — 2000-12-11
• A check, one might hope: Abbr. — 1999-06-07
• Postal letters? — 1997-04-03
• Env. stuffer — 1995-04-02