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LCCN Permalink Frequently Asked Questions

General Questions About LCCN Permalink

  1. What are LCCN Permalinks?
    LCCN Permalinks are persistent URLs for bibliographic records in the Library of Congress Online Catalog. These links are constructed using the record's LCCN (or Library of Congress Control Number), an identifier assigned by the Library of Congress to bibliographic and authority records.

  2. How can I use LCCN Permalinks?
    LCCN Permalinks offer an easy way to cite and link to bibliographic records in the Library of Congress Online Catalog. You can use an LCCN Permalink anywhere you need to reference an LC bibliographic record — in emails, blogs, databases, web pages, digital files, etc.

  3. How do I bookmark an LCCN Permalink record display?
    Just right-click on the LCCN Permalink web page and select appropriate options in your browser to copy the link, bookmark the page, or add the page to your favorites list.

  4. Does LCCN Permalink indicate whether an item is available at the Library of Congress?
    From the LCCN Permalink display, you can easily check the availability status of the item in the Library's collection by clicking on View LC holdings for this title in the: LC Online Catalog at the top of the web page. This link will take you directly to the bibliographic record and item status information in the LC Online Catalog.

  5. Does LCCN Permalink display non-Roman data found in LC Online Catalog records?
    Not at this time, but we expect to add this option in the near future.

  6. Are LCCN Permalinks available for Library of Congress authority records?
    Not at this time, but the Library is exploring options for adding this functionality.

  7. I have a valid LCCN. However, LCCN Permalink reports that the LCCN I submitted was not found in the LC Online Catalog. Why am I receiving this error message?
    LCCN Permalink retrieves and displays bibliographic records found in the LC Online Catalog. Not all LCCNs assigned by the Library of Congress, however, resolve to an LC Online Catalog record. The Library of Congress began assigning LC control numbers in 1898. Some LCCNs may have been deleted from the Catalog, some LCCNs from older printed cards may not yet have online records. LCCNs are also assigned before publication to items which the Library may subsequently decide not to add to its collections — including items cataloged by the National Library of Medicine or the National Agricultural Library, many large-print books, serials cataloged through the cooperative CONSER program, and items which received preassigned control numbers (PCNs). While LCCN Permalink may not find a bibliographic record in the LC Online Catalog, these LCCN may be represented in other library databases.

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Technical Questions About LCCN Permalink

  1. How does LCCN Permalink work?
    LCCN Permalinks are constructed using the following syntax:
    http://lccn.loc.gov/  followed by the normalized LCCN
    Examples: http://lccn.loc.gov/2003556443  or http://lccn.loc.gov/mm78044693
    These identifiers use the Library of Congress Online Catalog's Z39.50/SRU gateway to retrieve records formatted in MARCXML. The bath.lccn query searches both valid and cancelled LCCNs (MARC 21 fields 010a and 010z). Retrieved records are processed by XML stylesheets to create an LCCN Permalink display based on the Full Record display in the LC Online Catalog. LCCN Permalink also presents records in MARCXML, MODS, and Dublin Core formats. We anticipate adding additional formats (such as COInS for OpenURL linking) in the near future.

  2. How do I link directly to the MARCXML, MODS, or Dublin Core formats of LCCN Permalink?
    LCCN Permalink provides a qualified URL syntax to support direct persistent links to MARCXML, MODS, or Dublin Core-formatted bibliographic records. The qualifier must be added to the end of the LCCN Permalink URL. For example:  http://lccn.loc.gov/2003556443/mods

    The following LCCN Permalink qualifiers are currently supported:
    MARCXML
    MODS
    Dublin Core    		   /marcxml
    /mods
    /dc    		   
  3. How does LCCN Permalink normalize LCCNs?
    LC Permalink uses info:lccn URI specifications to normalize the standard LCCN syntax. Each LCCN has three components: a prefix, year, and serial number. Prefixes may be blank, or they may contain from one to three lowercase alphabetic characters (maintained in a controlled list). Year information is either two or four digits — two digits for LCCNs assigned through 2000, four digits for LCCNs assigned 2001 and later. LCCN serial numbers contain six digits.

    The info:lccn normalization removes hyphens, left-fills serial numbers with zeros, and removes spaces in LCCN prefixes. The resulting LCCNs may look different from LCCNs appearing in the MARC 010 fields of bibliographic records, in Cataloging-in-Publication data, or on printed catalog cards.
    Please format your LCCN using the following suggestions:
    If you are looking for...Enter the LCCN as...
    LCCN 89-456
    (assigned before 1/1/2001)    		89000456
    -- Omit spaces and hyphens.
    -- Make sure your LCCN is 8 characters long:
          Two numbers (representing a year) followed by six serial numbers.
          Add leading zeros if there are fewer than six serial numbers.
    LCCN 2001-1114
    (assigned after 12/31/2000)    		2001001114
    -- Omit spaces and hyphens.
    -- Make sure your LCCN is 10 characters long:
          Four numbers (representing a year) followed by six serial numbers.
          Add leading zeros if there are fewer than six serial numbers.
    LCCN gm 71-2450
    (assigned before 1/1/2001)    		gm71002450
    -- Omit spaces and hyphens.
    -- Make sure your LCCN is 9-11 characters long:
          Alphabetic prefix (1-3 characters)
          Two numbers (representing a year) followed by six serial numbers.
          Add leading zeros if there are fewer than six serial numbers.
    LCCN sn2006058112
    (assigned after 12/31/2000)    		sn2006058112
    -- Omit spaces and hyphens.
    -- Make sure your LCCN is 11-12 characters long:
          Alphabetic prefix (1-2 characters)
          Four numbers (representing a year) followed by six serial numbers.
          Add leading zeros if there are fewer than six serial numbers.
  4. My LCCN Permalink display contains some strange characters, such as boxes. Why?
    While bibliographic records retrieved from the LC Online Catalog will display correctly for most languages without changing your preferred browser settings, you may see boxes or incorrectly formatted characters if your browser is set to display mainly English language web pages. Instructions for checking your browser's font and character encoding settings can be found on the LC Online Catalog Help pages. LCCN Permalink displays are best viewed using Unicode fonts and the most current browser and operating system software.

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More Questions?

  1. What should I do when I receive a system error message?
    If LCCN Permalink is temporarily unavailable, please first try to refresh the display in your browser. If problems persist, please send a problem report to the Library through Ask a Librarian.

  2. How do I obtain an LCCN for my publication?
    The Library of Congress offers U.S. book publishers the service of assigning LCCNs to their prepublication titles through the Electronic Preassigned Control Number Program. Qualified publishers may also receive an LCCN as part of CIP data issued by the Cataloging in Publication Program. LCCNs are also assigned by the Library of Congress to items added to the Library's collections or cataloged as part of the cooperative CONSER program. As noted in FAQ Question 7, the assignment of an LCCN by the Library of Congress does not automatically ensure that a publication will be selected for Library's collections.

  3. Where can I go for help if this FAQ does not resolve my question or problem?
    If you are a researcher in a Library of Congress reading room, please ask the reference librarian on duty for help. You may also report problems by contacting the Library of Congress through Ask a Librarian.

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