In addition to David and Mitch's comments, Appendix J (Fall
'92) of the CEG states another key concept for usage of the
subdivision --Periodicals: "the subdivision --Periodicals is used
under headings assigned only to serials that conform to the more
restrictive definition of periodicals."
     The "restrictive definition of periodicals" for subdivision
usage also stated in App. J: "a publication other than a
newspaper that is issued at regular intervals in successive
parts, each of which bears a numerical or chronological
designation, and that is intended to be continued indefinitely."
(The definition of a periodical for the purpose of encoding fixed
field value S/T should not be confused with the above).
     Therefore, publications of annual reports of a corporate
body which report predominantly the activities and/or
administrative nature/operations of a body will have the
subdivision --Periodicals in the 610 field.  Please also refer to
CSB, No. 3 (winter 1979), P. 14 for additional guidelines on this
topic.  Mitch's reference to UC Berkeley's "unofficial"
definition of periodical is somewhat misleading.  Although an
Annual report of a Society may not appear in dentists' office,
the subdivision "--Periodicals" MUST appear on its bib record.
See the following LCCNs; 91-642066, 83-641354, 84-644984, 59-
4200 for confirmation.

Taemin Park
Serials Cataloger
Indiana University Library, Bloomington
Bitnet: Park@iubacs