Regarding Håvard's statement:
"The identifiers "scr" and "scc" will not be deleted or
"invalididated". Indeed, if a system properly implements ISO 639 it
should already allow "scr"/"hrv"/"hr" and "scc"/"srp"/"sr" as synonyms
for retreival purposes. Whether a data owner wants to change old data or
not, should be little more than a "cosmetic" issue."
This argument could be used in favor of the elimination of any of the
bibliographic identifiers where they differ from the terminological
identifiers. If we want to be careful in justifying a change only for
Serbian and Croatian, this would not be a good justification.
Library of Congress