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The NLM Versioned Source Identifiers List
NLM has a system list of such identifiers called Versioned Source Abbreviation (VSAB) identifiers, such as 'ICD9CM_2010', 'SNOMEDCT_20090101' and so on, for all terminologies known in the UMLS. The identifier list can be seen at
http://www.nlm.nih.gov/research/umls/metaa1.html
These identifiers are reliable, human readable, but it is not clear if they properly take account of versions. For example, two releases of SNOMEDCT are just two different strings like 'SNOMEDCT_2009_01_01' and 'SNOMEDCT_2009_01_07'. These are two releases of the same terminology and terms in data from each release should be comparable. Different variants of IDC10 exists, e.g. 'ICD10AM_2000', 'ICD10_1998' and so on. It appears that the part before the first underscore may be a reliable id of the terminology, and the remaining part can be taken as a version release id. If this can be trusted, then ids from this list encountered as part of coded data can be safely processed. In openEHR we use the form 'SNOMEDCT(20090101)', which makes the distinction between terminology id and release id easier to see, but the effect should be the same.