Historical clue formulations

• Hydrocarbon suffixes — 2012-08-22
• Chemical suffixes — 2012-08-09
• Hydrocarbon endings — 2011-11-25
• Scottish singletons — 2005-07-02
• Hydrocarbon suffixes — 2004-10-13
• Hydrocarbon suffixes — 2004-04-06
• Hydrocarbon suffixes — 2000-10-23