Library of Congress
Under "X00 Personal Names - General Information - Input Conventions - Spacing," the MARC 21 Format for Bibliographic Data states "A name portion containing an open-ended date ends with one space when it is followed by a subject subdivision portion" and the MARC 21 Format for Authority Data states "A name portion containing an open-ended date ends with one space when it is followed by a subject subdivision portion or additional subfield data."
Appendix D (punctuation), p. 3 of the Subject Cataloging Manual: Subject Headings (dated August 2000) states: "Do not add a blank space after an open date that is followed by a $v, $x, or $t subfield." This change was made after installation of the LC ILS, which removes "extra" spaces that abut subfield codes (other than in field 010 (Library of Congress Control Number). This statement will be labeled LC practice when the page is revised for the manual's 2001 Update Number 1. The generalization is "Follow MARC 21 practice to the extent a local system permits."
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