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punctuation: No punctuation mark precedes this subfield, except for a decimal point before an arabic numeral.
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First $$a: This is a measurement of the linear feet of the item as it will sit on the shelf once it has been end-processed. It precedes the item-extent $$a with no punctuation. For items that consist of a few sheets, the The measurement entered will depend on how they the item will be housed; check end-processing documentation for measurements of standard boxes, pre-fabs, and other containers. If necessary, estimate the approximate linear feet by measuring the width of the volume or height of the stack of leaves. Note: 1/4 inch is approximately .02 linear feet.
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300 __ $$a .04 linear feet $$a (1 volume) [typical description for 1 small pre-fab folder]
300 __ $$a .08 linear feet $$a (1 volume) [typical description for 1 medium pre-fab folder]
300 __ $$a .05 linear feet $$a (1 letter; 2 folded sheets)
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In cases where a page count for a modern, bound manuscript is necessary or desirable, we use the style shown in the examples below. If the manuscript is already reasonably correctly foliated or paginated, use that number. Otherwise, if feasible, count the leaves disregarding blanks at front and back. Any large number of blank pages in the manuscript should be counted in the foliation but mentioned as blank in a 500/505 note. Do not use square brackets but rather express in words when numbered and unnumbered leaves are both counted.
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For medieval and renaissance manuscripts, count all leaves or sheets. Do not rely upon any numeration present in a manuscript, whether original or added later. Supply any such collation in a 500 note. “Include Include in the extent original raised flyleaves, original flyleaves used as pastedowns or free-end endpapers, and blanks. Do not include in the total extent canceled leaves, or modern flyleaves and endpapers .” (AMRMM 5B2). The extent is reported using the following style:
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300 __ $$a .2 linear feet $$a (1 volume) : $$b illustrations
If a single-item manuscript includes a manuscript or printed map, it should be listed here.
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punctuation: Preceded by a space and a plus sign (‘"+’").
This subfield is intended to describe accompanying material other than that listed in the subfield $$a. It is a loose field for single-item manuscripts, but can be useful. It can include a note about a seal accompanying a medieval document, or a photograph enclosed with a letter. Use this field for any envelopes accompanying letters.
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