Changes in the frequency of issuance are common. CONSER practice is to record all frequency changes in the bibliographic record with the current frequency recorded in the 310 and former frequencies in 321 fields beginning with the earliest most recent to the latestoldest. Capitalize the first word of each field but do not include a period at the end of any field. Update the Fixed-length field 008/18-19 with the current (new) frequency with every change in frequency.
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