21.9.  Adding optional elements

Cataloging record requirements exist to establish the data set (or group of MARC 21 fields) that serve as the basis for what is commonly needed by participating members.  The minimal-level requirements in CONSER represent the set of bibliographic elements that all records must contain, with core and full levels representing additional requirements.  All members are also free to add any optional data as applicable.  A core record, for example, can include any applicable optional element, in addition to the set of required fields.  Once the record includes all the elements that are required for the full-level record, its encoding level may be increased to full (encoding level “#”).  Information is never removed from a record simply because it is not required.

CONSER does not include a standard classification number as a required element in its records, yet many members do include at least one kind of classification number (i.e., fields 050, 055, 060, 070, 080, 082) ( FN 8).  CONSER does not consider it practical to require its members to add classification numbers to its records since many classify only portions of their serial collections.  As with other optional elements, follow all relevant instructions when adding a classification number.

CONSER affiliate members add a variety of data to serial records.  Abstracting and indexing information, subscription information, publishing information, and fields used to close-off records are routinely added by commercial vendors that participate in CONSER.  Some fields added by affiliate members are not required of all members yet CONSER does consider the information significant to the extent that a distinct membership level is intended to support the creation and maintenance of such data in program records.

Record Modified by Chemical Abstracts Service

See also:

Module 21.  Modifying Records