Hierarchy classification:

1. top of the aat hierarchies
2. Associated Concepts Facet
3. Associated Concepts (hierarchy name)
4. multidisciplinary concepts
5. [dates and dating systems]
6. dates (spans of time)
7. [dates by century or millennium]

Anotations

Scope note:

Identification of years as Before Common Era or Before Current Era or Before Christian Era. BCE uses the same numbering as BC (Before Christ) and corresponds to the Gregorian Calendar. "CE" and "BCE" are placed after a year number, and BCE is now most often used instead of BC especially in scientific writing.