31.15.1.  Description

Field 856 identifies the electronic location of the serial from which it is available and information needed to access the serial by the method identified by the first indicator value (email, HTTP, FTP, telnet, dial-up).  Information in the field should be sufficient to connect to a service, transfer files electronically, subscribe, or access issues of an electronic journal or newsletter.  Because this information may change, it is important that it be recorded from the most recent issue of the serial.  For detailed instructions on how to construct the 856 field, see the CONSER Editing Guide .  Also helpful are the Guidelines for the Use of Field 856, http://www.loc.gov/marc/856guide.html, prepared by the Network Development and MARC Standards Office of the Library of Congress.

Use of this field varies depending on the local catalog system.  Some systems use the field as a "hot link" to connect the user with the online resource through the bibliographic or holdings record.  Other systems generate OPAC displays to enable users to better understand information presented in the field.

Field 856 has subfields defined to hold a variety of data and instructions.  Commonly used subfields of field 856 are listed below (there is no preferred order of these subfields):

$u, which holds a Uniform Resource Identifier (URI), such as a URL or URN;

$3, which contains information that specifies the part of the bibliographic item to which the field applies, when there is not a fully one-to-one relationship between the 856 and the resource described in the record; and

$z, which has a note, intended for public display, related to the electronic location or identifier in the 856 field.

a.  Multiple locations

Deciding which and how many 856 fields to record for an online serial can be a difficult decision and depends on several factors.  These include the number and types of URIs or other access methods available to the cataloger at the time of cataloging, local policies regarding the provision of 856 fields, and the need for widely accessible 856 fields on shared OCLC and CONSER records.  Frequently, a cataloger will need to record a different access method locally than what is recorded in the CONSER record.  The institution may access licensed resources through unique URIs which other institutions would not be able to use.  In general, for the OCLC/CONSER record, use more widely available access methods in the OCLC record over methods which provide local institutional access only (an imbedded institutional ID in a URI, for example).  Pages that present the user with a password and user id logon form probably are less convenient for users than pages that provide direct access to the serial, but sometimes are the only access methods available for recording in the record.  If the content of a serial is spread over several locations, e.g. early volumes have one URI, later volumes have a different URI, it might be necessary to add several 856 fields to cover the entire content of the serial.  The range of issues available from these sites can be given in $3 of the 856 field (see examples below in CCM 31.15.2).

When there are multiple providers, URIs for each may be given on the aggregator-neutral record.

b.  Multiple locations within a site

Often, the problem is having too many access methods from which to choose.  Should the cataloger use a URI which points to a provider’s home page, a specific journal’s home page, table of contents for all issues of the serial, particular issues of a serial?  The site’s structure and the access available on various pages give the cataloger clues in making this decision.  Pointing to a page which gives the user access to all the issues either through a table of contents or search interface provides access to the serial content without having to navigate several pages.  On the other hand, access to some or all of these pages in publisher or distributor sites may be restricted to subscribers only.  In such cases, it is preferable to point to a higher level page (a journal home page, for example) which at least provides an unregistered viewer information about the serial, subscription information, a password prompt, and perhaps sample issues or portions of the serial that are made available to non-subscribers.  It is important to consider the function of pages in the site design as well.  Many publishers provide journal home pages that are intended as a direct portal to the serial content, clearly identify the title, and may provide longer term stability than pages at other levels.

c.  Mirror sites

With some serials the cataloger is faced with multiple "mirror" sites--alternative locations for accessing a Web site.  Selecting how many of these to record also depends on the limits of the CONSER record and needs of the cataloging agency in providing access to its constituency.  Providing several sites on a record helps assure an institution’s access when one server is busy or where agreements between distributors, publishers, etc., make it preferable to provide users with multiple mirror locations.  On the other hand, recording of all possible mirror sites on the CONSER record may not be practical.  Besides the time involved in recording multiple 856 fields, there is a concern that more maintenance is involved if related mirror sites change at the same time.  Ultimately, the decision on how many mirror sites to add to a record should focus on the needs or policies of the cataloging agency, shaped by the need to provide widely available access methods on the CONSER record.  A cataloging agency, for example, could decide to record mirror sites in its home country and other mirror sites it deems necessary to assure its users access.  When added to the CONSER record, multiple mirror sites which give identical access from different locations could be labeled as such:

856 40 $z Access from the U.S.:$u http://www.us...

856 40 $z Access from Europe: $u http://www.europe...

d.  File formats

The 856 field is repeatable in two other ways:  1) if an electronic serial is available by more than one access method; and 2) if there are multiple file formats with different file names or groups of files.  Separate 856 fields may be needed for each access method (e.g., World Wide Web, email, etc.) by which the serial is available.  Separate 856 fields for document formats may not be needed because more than one document format is often available from the same access method.  The first indicator of field 856 defines access method; for example, first indicator "4" shows access is via HTTP.  The second indicator identifies the relationship of the location or identifier in the 856 field to the item being described in the record as a whole; for example, second indicator "0" means the 856 field is for the same resource covered by the record as a whole, while "1" indicates the 856 is for an electronic version of the item described in the record.

31.15.2.  Uses of field 856 in CONSER records

Field 856 is given in CONSER records in the following circumstances:

1)   On the record for a remote access serial to cite the location of that serial.  Use second indicator "0."  In the aggregator-neutral record, URIs of all the providers distributing the serial are given.  If the contents of the serial are split among multiple sites (whether multiple providers or several locations at one provider site), subfield $3 is used to cite issues found at a particular location:

856 40 $3 Current issues available from the Publications Page of the ASA Web site $u http://www.asanet.org/pubs/pubs.html

856 40 $3 Archived issues $u http://www.asanet.org/footnotes/previous.html

856 40 $3 1994 $u http://www.computer.org/conferences/sc94/sc94home.html

856 40 $3 1995 $u http://www.supercomp.org/sc95/proceedings/

856 40 $3 1989-1991, 1993-1994 $u http://www.acm.org/pubs/contents/proceedings/series/sc/

856 40 $3 Abstracts: v.3(1998)-v.4(1999). Full text: v.5(2000)- $u http://...

2)  On the record for a printed (or other format) serial to cite the location of partial contents or related information, such as summaries, abstracts, tables of contents, or subscription information.  Subfield $3 should be used to identify the part that is online.  Use second indicator "1" whenever the URI points to any part of the electronic version.  This includes Web sites which give access to some parts of the print material, even if it's repackaged in a substantial way.  For example, a Web site which gives only the table of contents of a journal or only abstracts would still be indicator 1 because the site's content is essentially a version of the printed material.

856 41 $3 Summaries and index $u http:// ...

3)  On the record for a printed or other format serial when there is an online version, regardless of whether the online version is separately cataloged or not.  Use second indicator "1."

4)  For related resources that do not represent the serial cataloged, its online version, or a part of the serial.  Common examples would be an organizational home page or publisher's Web site.  If an organizational home page contained a 10-year index to a journal or the tables of contents of several titles, this would be a related Web site.  Use second indicator "2."

856 42 $3 Related resource: home page of the Health Physics Society: $u http://www.health-physics.com

31.15.3.  Construction and coding

Depending on the mode of access, different subfields may be necessary in the 856 field.  Subfield $u may be used instead of or in addition to other subfields.

856 00 $z Email subscription $u mailto:listserv@loc.gov $i subscribe $f CONSRLIN

For additional guidelines on coding the 856 field see Guidelines for the Use of Field 856 from Network Development and MARC Standards Office, Library of Congress:  http://www.loc.gov/marc/856guide.html.

31.15.4.  Volatility of access information

Without the regular examination of individual issues which is a natural by-product of check-in and inventory control, the URI for an electronic publication on a catalog record may quickly become inaccurate.  Link checking software run locally can provide information about broken links but requires regular processing and follow-up work to determine if changes are needed.  Serials management companies also provide maintenance for URIs as a part of their services for maintaining subscription information for online serials.  Use of persistent identifiers or handle systems is another method to provide a mechanism for URI maintenance.  An example of a persistent identifier is the PURL (persistent uniform resource locator), which allows libraries to update changes in URIs on a PURL server without needing to change URLs in catalog records.  Link diagnostic notifications from the OCLC Connexion’s Resource Catalog are another option OCLC libraries have for learning about changed URIs and making updates.

What should a cataloger do when encountering a record that has institution-specific access methods recorded in the 856 fields, links that are no longer valid, or links that point to a less than ideal location?  For obvious errors in the access method (for example, if a typo prevents a URI from working correctly), the cataloger should make corrections.  Where it is difficult to determine the usefulness of an existing access method because of access restrictions, lack of a password to logon, uncertainty of whether links are broken temporarily or permanently, etc., it is best to leave the 856 field on the record and add additional 856 fields.  Even for access methods that appear to be invalid, there may be an advantage to leaving them on the record.  The 856 field in many systems, including OCLC, is a searchable field.  It is possible for an inactive address to give searchers clues about title changes, content changes, and former resource providers.  If the only link appearing on the CONSER record is an invalid link, it can be left on the record and labeled as invalid in the subfield $z of the 856 field.  Note that the second indicator is blank and that the non-working URL is maintained in subfield $u of the 856.  This coding differs from LC practice documented in LCRI 9.7B where the non-working URL is moved to a subfield $z so that it does not appear on LC's link checking reports repeatedly.  The example below is based on a recommendation from OCLC and is derived from current system indexing needs and OCLC's electronic address checking software.

856 40 $z Link no longer valid as of Dec. 4, 2000 $u http://www...

31.15.5.  PURLs in CONSER records

PCC institutions are using PURLs in records for free online serials and other online resources.  The successful maintenance of access information for these resources depends on the fact that the PURL is added to the record and never (except in rare instances where a mistake has been made or a duplicate PURL assigned) changed or deleted.  Therefore CONSER members have agreed not to delete PURLs found on records.

GPO has been adding PURLs to records for government documents for several years and many CONSER authenticated records contain them.  Current GPO practice is to record the URL of an online version of a work in the 530 (on a single record approach print record) or in the 538 of the online publication being cataloged.  These notes give the original URL and the date on which a PURL was established for the title.

The PCC PURL Project allows participants to cooperatively maintain URLs for freely available Web resources.  A PURL server, hosted by OCLC, is used to enter and maintain URLs.  Participants receive weekly error reports of changed or broken URLs and make changes to the URL stored on the PURL server without needing to change the record; the PURL in the record will point to the correct changed URL in the PURL server.

PCC institutions are not required to use the PURL server or to be part of the PCC PURL Project.  However, those who are cataloging in OCLC are encouraged to create a PURL and add it to the OCLC record.  Any PCC participant can register on the PURL server; the participant's OCLC authorization number is used for logging on.  Documentation and guidelines for the participants are posted on the project Web site (http://www.loc.gov/acq/conser/purl/main.html).  Currently both the PURL and the URL are being added to the 856, the PURL in the first subfield $u and the URL in a subsequent subfield u.  For example:

856 4# $u http://bibpurl.oclc.org/web/1022 $u http://www.mihan.net/

See also:

Module 31.  Remote Access Electronic Serials (Online Serials)