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Resource Description Formats

Digital Library Standards

Information Resource Retrieval Protocols

Information Resource Retrieval Standards

  • ISO 639-2
    Codes for representing names of languages (Part 2: Alpha-3 code)
  • ISO 639-5
    Codes for representing names of languages (Part 5: Alpha-3 code for language families and groups)
  • ISO/DIS 25577
    Information and documentation (MarcXchange)
  • ISO 20775
    Schema for holdings information

International Standard Serial Number (ISSN)

The U.S. ISSN Center, part of the international ISSN Network, assigns International Standard Serial Numbers (ISSN) to serials published in the U.S. The ISSN is a standard identifier for serials (e.g., journals, magazines, newsletters, newspapers, annuals) whether published in print, online or other media. Each medium version is assigned a separate ISSN.
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Metadata for Digital Content

Developing institutional policies and standards at the Library of Congress.
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Recommended Formats Statement

Best practices for ensuring the preservation of, and long-term access to, the creative output of the national and the world in both analog and digital formats.
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