If research is done in order to make additions or changes to an authority record and sources are searched that do not provide information about the heading, cite them in a 675 field.

If the authority record being modified already contains a 675 field, add newly searched source(s) at the end.  If it does not, formulate one listing  source(s) searched.

The 675 field may also be added to an existing authority record in order to justify earlier/later headings (5XXs).

See also:

Section II:  Additions and Changes to Authority Records