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b B.C. date involved (use 046 field)
i inclusive dates for a collection. Use this for a group of distinct items, e.g. letters, that are bound together.
s single known or probable date
m multiple dates. Use this for a work that is executed over a period of time that can be specified. This would include a manuscript that contains annotations or additions made after made after its first copying.
n date unknown (DACS asks for you to attempt to date, even with a broad range, consult before using)
q questionable date. Use this only for a single date that can be narrowed to within a range of yearsany approximate date range, when exact date is unclear.
(07-10) Date 1
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ca. 1640-1649 s 164u blankq 1640 1649
ca. 1600-1699 s 16uu blank1699 q 1600 1699
(15-17) Place of publication, production, or execution.
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