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NLM Bibliographic Products Available in XML Format

Bibliographic products available in XML format include CatfilePlus in XML and Serfile in XML.

CatfilePlus in XML
CatfilePlus in XML is derived from the MARC 21-formatted records in LocatorPlus and contains XML representations of :

The records of both types which have been created or modified in the same timeframe are integrated into a one file and distributed in a single product.

Because the XML records are derived from LocatorPlus records, the search criteria for CatfilePlus in XML are based on fields in LocatorPlus and are identical to those for CatfilePlus in MARC 21 format. "Ownership" of records in CatfilePlus can be determined from the owner attribute in the top-level element, <NLMCatalogRecord>, which is set to either NLM (for NLM cataloged records) or a collaborative partner. If the record is "shared" between NLM and/or one or more collaborative partners, the additional owners are represented by the owner attributes associated with <CollaborativePartnerDate>.

CatfilePlus in XML is made available to licensees to ftp on a monthly basis. All records that were completed by NLM and "AUTHorized for distribution", those with cataloging-in-publication information (CIP), all records substantially revised by NLM, as well as all records released by the collaborative partner organizations or substantially revised by them are included in the monthly CatfilePlus in XML distribution.

The average number of records in the CatfilePlus in XML monthly distribution is estimated to range from 4,000-6,000 records. In addition, the backfile of slightly more than 1,000,000 records is available to licensees, if desired.

Those interested in licensing CatfilePlus in XML may first wish to obtain and examine the relevant NLM DTDs and sample files of Catfile in XML data.

Data element descriptions applicable to CatfilePlus in XML are available at http://www.nlm.nih.gov/bsd/licensee/catrecordxml_element_desc2.html. A description of attributes for these elements is available at http://www.nlm.nih.gov/bsd/licensee/catrecordxml_attributevalues_alpha2.html.

Serfile in XML
Serfile in XML contains all XML-formatted versions of all serial bibliographic records in LocatorPlus, whether or not they have been cataloged by NLM. Because the XML records are derived from LocatorPlus records, the search criteria for Serfile in XML are based on fields in LocatorPlus and are identical to those for Serfile in MARC 21 format, where serials are identified with the Leader byte 07 values 's' or 'b'.

Serfile in XML is made available for licensees to ftp on a monthly basis. All records for serials which were added or updated in any way during the previous month are included in the monthly Serfile in XML distribution. The average number of records in the Serfile in XML monthly distribution generally ranges between 1,000-3,000 records per month. In addition, the backfile of approximately 120,000 records is available to new licensees, if desired.

Those interested in licensing Serfile in XML may first wish to obtain and examine the relevant NLM DTDs and sample files of Serfile in XML data.

Data element descriptions applicable to Serfile in XML are available at http://www.nlm.nih.gov/bsd/licensee/catrecordxml_element_desc2.html. A description of attributes for these elements is available at http://www.nlm.nih.gov/bsd/licensee/catrecordxml_attributevalues_alpha2.html.

An alternative product, the List of Serials Indexed for Online Users (LSIOU), a subset of Serfile, is available in XML and PDF format. The LSIOU provides basic bibliographic information for only the serials from which articles are indexed with the MeSH® vocabulary and cited in MEDLINE (does not cover OLDMEDLINE titles). See http://www.nlm.nih.gov/tsd/serials/lsiou.html for more information. Please note that the LSIOU uses its own DTD which is different from the DTD used for SERFILE.

Sample NLM Data
Samples of CatfilePlus in XML format and Serfile in XML format are available for prospective NLM data licensees. A license agreement is not needed for sample data. For instructions on how to obtain the sample files of XML products, refer to Sample NLM Data.

How to Lease
NLM leases CatfilePlus in XML and Serfile in XML to U.S. individuals or organizations; to its formally recognized International MEDLARS Centers; and to non U.S. individuals or organizations solely for research purposes (limited to internal use with no commercial applications). For purposes of leasing NLM databases, the following criteria must be met to be considered a U.S. organization: the organization is incorporated in U.S.; the signing official is a principal in the organization who is located in the U.S. and is not simply an authorized agent; and any financial payment to the NLM is issued from an U.S. account (although there are no fees for leasing NLM databases in the foreseeable future).

Complete and return the applicable License Agreement and Intended Use Worksheet.

Last updated: 07 April 2008
First published: 02 August 2004
Metadata| Permanence level: Permanence Not Guaranteed