A chronological subdivision brings out the time period of the subject represented by the main heading or indicates the publication date of the document. The chronological subdivision may follow the main heading directly or appear as a sub-subdivision under another subdivision. Some headings are subdivided chronologically. Chronological subdivisions are provided under main headings representing subjects which lend themselves to chronological treatment, most frequently in social sciences or humanities topics, particularly in history. The chronological subdivisions used under each heading either correspond to generally recognized epochs in the literature of the field or represent spans of time frequently treated in books. Examples

8.14 References

See also:

8.1 Types and functions