684 Auxiliary Instruction Note (R) (Variable Data Field)
Field definition and scope: This field contains a note which gives information from, or a reference to, a section of a classifier's manual or other documentation. An auxiliary instruction note provides advice for classifying in difficult areas, and describes policies and practices that may accompany a classification schedule . Examples of auxiliary instructions may be found in the Dewey Decimal Classification manual or other documentation intended to be used with a classification schedule. A separate 684 note is used when different types of notes are recorded, identified by the first indicator.
The information in this field is primarily intended to guide classifiers and is often not written in a form adequate for public user display.
Field 684 is repeatable .
Guidelines for applying Content Designators:
Indicators
Second Undefined; contains a blank (#)
Subfield Codes
$a Classification number - Single number or beginning number of span (R)
$c Classification number - Ending number of span (R)
$y Table identification - Schedule (R)
$z Table identification - Table number (R)
$5 Institution to which field applies (R)
$8 Link and sequence number (NR)
Conventions: Dewey Decimal Classification (Scheme-Specific)
Related USMARC fields or documents:
763 Internal Subarrangement or Add Table Entry
See also:
