I'm addressing this to the list since other people may wonder too.
I've found that even though SERLINE no longer has the locations
field, it still does have the AI field, which tells you where
the journal is indexed (e.g. IM, BA, PA).  This is incomplete, though,
in that a journal may no longer be indexed by PA, for example, but
this does give a pretty good indication of where to try.
Martha Stone, Treadwell Library, Mass. General Hospital, Boston, MA 02114
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