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Quick Reference Cards and Guides

CA section thesaurus (PDF) (~138K)
CAS roles in CA^SM/CAplus^SM (PDF) (~160K)

STNotes

• Searching pre-1967 references in CAplus and CA (PDF) (STNote 26; Revised 7/05)
• The CA Lexicon on STN (PDF) (STNote 25; Revised 12/04)
• Patent Family Information in CAplus (PDF) (STNote 19; 11/98; Reviewed 3/05)

User Guides

• Using CAS Databases on STN (self-instructional user guide) 

User References

• 15CI General Subject Heading Changes and Additions (HTML) (4/02)  
• Naming and Indexing of Chemical Substances for Chemical Abstracts^TM (PDF) (2007) (~2.7 MB) (formerly Appendix IV of the CA Index Guide^SM) 
• Nomenclature Changes for CA Index Names (2007) (PDF)
• Changes in the Indexing, Registration, and Naming of Chemical Substances for the 14th CI (2002) (PDF) (HTML)
• CA Sections
• CAS Standard Abbreviations (PDF) (HTML)
• CAS Coverage of Patents