Understanding Rx Norm
Why Symedical?
SNOMED-CT Essentials and Core Subset Overview (2009)
Provides a high level overview of the SNOMED-CT terminology data files.
SNOMED-CT to ICD9 Mapping Files (2009)
provides a high level overview of how you can use the option SNOMED-CT cross map file to help with mapping to ICD9-CM codes.