Could someone please let me know the correct usage of angle brackets in
bibliographic records?

I have found an instruction in module 13, p. 8 of the CONSER cataloguing manual
to use angle brackets when the exact beginning/ending designation is not known,
however I am not sure if this is CONSER policy or general cataloguing practice.
I have checked AACR2, LCRI, ISBD(S) and even the Chicago manual of style but to
no avail. Any help would be greatly appreciated.

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John Nicklen                              E-mail: j.nicklen@admin.nls.uk
Head of Serials Cataloguing Unit          Phone:  +44 (0)131 226 4531
National Library of Scotland              Fax:    +44 (0)131 220 6662
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Edinburgh EH1 1EW
Scotland