> What do other serial catalogers do when they encounter a monthly which gives
> along with the month date a day date (or annual which includes month or
> month and day with the year)?

I include the superfluous date. I suppose that for each catalog user
who looks for a "11 Aug. 1991" issue when "25 Aug. 1991" was cataloged
there might be one who looks for the "Aug. 1991" issue if that is
catalogued and get upset if all they find is the "25 Aug. 1991" issue.
The searcher will also get another hint about frequency from the 310
and the fixed fields (however they may be displayed in the particular
system they are using) which might prevent a hunt for a non-existant
issue. Then again.... !

Using the full date also help us (other catalogers) know that we, in
fact, _are_ looking at the same issue you had in hand when you created
or modified the record.

...Eric Celeste
   MIT Libraries