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The use of the 506 field indicates that ETDs and North Broad Press publications are free-to-read. The format of this field is determined by LC’s Marc Standards and Access Restrictions Term Source Codes documentation.
The 506 field will not be applied to bibliographic records for other open access electronic resources provided by outside vendors such as the Open Textbook Library or the Directory of Open Access Journals.
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Jeff Edmunds & Ana Enriquez (2020). “Increasing Visibility of Open Access Materials in a Library Catalog: Case Study at a Large Academic Research Library,” Journal of Library Metadata, 20:2-3, 127-154, DOI: 10.1080/19386389.2020.1821946
Note: Restrictions to access for purchased and subscription electronic resources limited to Temple University affiliated patrons will continue to be designated in a local 590 note. In Alma, this note can be added to records using the “Add 590 for electronic research records” Normalization Rule.
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