unique Accession Number in temporary citations prefs

After choosing Accession Number instead of Record Number in temporary
citations preferences, EndNote X1 erroneously treats certain references
as ambiguous, even if they have an unique Accession Number and a unique
first author.
Example: 
There is one record with Accession Number 56 in the database, which to
any human is absolutely unique, there is no other author anywhere called
"Ma". The author field in this record lists as first author "Ma, K. K."
on a line of its own, co-authors are also all on one line (record
imported from PubMed via EndNote, PMID=16452325, NOTE: the accession
number was changed manually to 56).
On formatting the text containing "... see also {Ma, 2006, 56} and ..."
ENX1 treats this citation as ambiguous and offers eleven records to
choose the correct one from. The only thing that  these eleven records
have in common is the presence of the two adjacent characters "5" and
"6" ANYWHERE in the record (e.g. "1245687", or "56.5%", or "56th Ave.",
or "p. 563", or 56 in the Volume field, etc.).

Is this a bug or a misconception on my side?


Regards,

Andreas U. Freiburghaus, M.D.

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