First Indicator | Second Indicator |
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Access method # - No information provided 0 - Email 1 - FTP 2 - Remote login (Telnet) 3 - Dial-up 4 - HTTP 7 - Method specified in subfield $2 |
Relationship # - No information provided 0 - Resource 1 - Version of resource 2 - Related resource 8 - No display constant generated |
Subfield Codes | |
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Contains the information needed to locate and access electronic information pertaining to a community service such as the service or event website or related resources. Subfields $y (Link text) and $z (Public note) may be used to specify the type of electronic information.
Field 856 is repeated when the location data elements vary (the URL in subfield $u or subfields $a and $d, when used). It is also repeated whenever the electronic filename varies (subfield $f), except when a single intellectual item is divided into different parts for online storage or retrieval.
See the Guidelines for the Use of Field 856 for a more thorough discussion on the use of field 856.
First Indicator - Access method
Value that defines the access method to the electronic resource. If the resource is available by more than one access method, the field is repeated with data appropriate to each method. The methods defined are the main TCP/IP (Transmission Control Protocol/Internet Protocol) protocols.
When recording a URL in subfield $u the value corresponds to the access method (URL scheme), which is also the first element in the URL string.
Access to the electronic resource is through electronic mail (email). This access includes subscribing to an electronic journal or electronic forum through software intended to be used by an email system.
Access to the electronic resource is through the File Transfer Protocol (FTP).
Access to the electronic resource is through remote login (Telnet).
Access to the electronic resource is through a conventional telephone line (dial-up). Additional information in subfields of the record may enable the user to connect to the resource.
Access to the electronic resource is through the Hypertext Transfer Protocol (HTTP).
Access to the electronic resource is through a method other than the defined values and for which an identifying code is given in subfield $2 (Source of access).
Second Indicator - Relationship
Value that identifies the relationship between the electronic resource at the location identified in field 856 and the item described in the record as a whole. Subfield $3 is used to provide further information about the relationship if it is not a one-to-one relationship.
No information is provided about the relationship of the electronic resource to the item described by the record.
Electronic location in field 856 is for the same resource described by the record as a whole. In this case, the item represented by the record is an electronic resource. If the data in field 856 relates to a constituent unit of the resource represented by the record, subfield $3 is used to specify the portion(s) to which the field applies. The display constant Electronic resource: may be generated.
Location in field 856 is for an electronic version of the resource described by the record. In this case, the item represented by the record is not electronic but an electronic version is available. If the data in field 856 relates to a constituent unit of the resource represented by the record, subfield $3 is used to specify the portion(s) to which the field applies. The display constant Electronic version: may be generated.
Location in field 856 is for an electronic resource that is related to the item described by the record. In this case, the item represented by the record is not the electronic resource itself. Subfield $3 can be used to further characterize the relationship between the electronic item identified in field 856 and the item represented by the record as a whole. The display constant Related electronic resource: may be generated.
$a - Host name
Fully qualified domain (host name) of the electronic location. It contains a network address which is repeated if there is more than one address for the same host.
856 | 1#$aharvada.harvard.edu$aharvarda.bitnet |
$c - Compression information
Information about the compression of a file; in particular, whether a specific program is required to decompress the file.
Subfield may be repeated if two compression programs are used, noting the latest compression first.
856 | 1#$amaine.maine.edu$cMust be decompressed with PKUNZIP$fresource.zip$s16874 bytes |
$d - Path
Path, the series of logical directory and subdirectory names that indicate where a file is stored. The filename itself is recorded in subfield $f. This may be a surrogate path leading the user to the host where complete and current access information is stored in a locator table.
856 | 1#$awuarchive.wustl.edu$d/aii/admin/CAT.games$fmac-qubic.22.hqx |
$f - Electronic name
Electronic name of a file as it exists in the directory/subdirectory indicated in subfield $d on the host identified in subfield $a. Subfield $f may be repeated if a single logical file has been divided into parts and stored under different names. In this case, the separate parts should constitute a single item. In all other cases, a file that may be retrieved under different filenames contains multiple occurrences of field 856, each with its corresponding electronic name in subfield $f. A filename may include wildcard characters (e.g., * or ?) if applicable. Use subfield $z to explain how files are named, if needed.
856 | 1#$awuarchive.wustl.edu$dmirrors/info-mac/util$fcolor-system-icons.hqx | ||||||||
856 | 0#$akentvm.bitnet$facadlist file1$facadlist file2$facadlist file3 |
$m - Contact for access assistance
Name of a contact for assistance in accessing a resource at the host specified in subfield $a. For addresses relating to the content of the resource itself (i.e. the item represented by the title recorded in field 245) rather than access assistance, field 270 is used. If the address data is the same, use field 270.
856 | 2#$agopac.berkeley.edu$mRoy Tennant |
$o - Operating system
Operating system used by the host specified in subfield $a may be indicated here, for informational purposes. Conventions for the path and filenames may be dependent on the operating system of the host. For the operating system of the resource itself (i.e., the item represented by the title recorded in field 245), rather than the operating system of the host making it available, field 753 (Technical Details Access to Computer Files), subfield $c (Operating system) is used.
856 | 1#$aseq1.loc.gov$d/pub/soviet.archive$fk1famine.bkg$oUNIX |
$p - Port
Portion of the address that identifies a process or service in the host.
856 | 2#$amadlab.sprl.umich.edu$p3000 |
$q - Electronic format type
Identification of the electronic format type, which is the data representation of the resource, such as text/html, ASCII, Postscript file, executable application, or JPEG image. Electronic format type may be taken from enumerated lists such as registered Internet Media Types (MIME types).
The intent of specifying this element is to provide information necessary to allow people or machines to make decisions about the usability of the encoded data (what hardware and software might be required to display or execute it, for example). The electronic format type also determines the file transfer mode, or how data are transferred through a network. (Usually, a text file can be transferred as character data which generally restricts the text to characters in the ASCII (American National Standard Code for Information Interchange(ANSI X3.4)) character set (i.e., the basic Latin alphabet, digits 0-9, a few special characters, and most punctuation marks) and text files with characters outside of the ASCII set, or non-textual data (e.g., computer programs, image data) must be transferred using another binary mode.)
856 | 1#$aarchive.cis.ohio-state.edu$dpub/comp.sources.Unix/volume 10$fcomobj.lisp.10.Z$qbinary |
$s - File size
Size of the file as stored under the filename indicated in subfield $f. It is generally expressed in terms of 8-bit bytes (octets). It may be repeated in cases where the filename is repeated and directly follows the subfield $f to which it applies. This information is not given for journals, since field 856 relates to the entire title, not to particular issues.
856 | 1#$awuarchive.wustl.edu$dmirrors/info-mac/util$fcolor-system-icons.hqx$s16874 bytes | ||||||||
856 | 0#$akeptvm.bitnet$facadlist file1$s34,989 bytes$facadlist file2$s32,876 bytes$facadlist file3$s23987 bytes |
$u - Uniform Resource Identifier
Uniform Resource Identifier (URI), which provides electronic access data in a standard syntax. Field 856 is structured to allow for the creation of a URL from the concatenation of other separate field 856 subfields. Subfield $u may be used instead of those separate subfields or in addition to them. Subfield $u may be repeated only if both a URN and a URL or more than one URN are recorded.
This data can be used for automated access to an electronic item using one of the Internet protocols or by resolution of a URN. Field 856 is repeated if more than one URL needs to be recorded.
856 | 1#$uftp://path.net/pub/docs/urn2urc.ps | ||||||||
856 | 7#$uhttp://lcweb.loc.gov/catdir/semdigdocs/seminar.html$2http |
$v - Hours access method available
Hours that access to an electronic resource is available at the location indicated in this field. If the record is for a system or service, the hours of availability are recorded in field 307 (Hours, etc.). This subfield is only used to record hours of availability of the specific location indicated in field 856.
856 | 2#$apac.carl.org$mCARL Situation Room$m[email protected]$v24 hours | ||||||||
856 | 3#$alocis.loc.gov$m[email protected]$vM-F 6:00 a.m.-21:30 p.m. USA EST, Sat. 8:30-17:00 USA EST, Sun. 13:00-17:00 USA EST |
$w - Record control number
System control number of the related record preceded by the MARC code, enclosed in parentheses, for the agency to which the control number applies. The data in the subfield links field 856 to the MARC record having the same data in a control number field. See Appendix G for a listing of organization code sources used in MARC 21 records.
$x - Nonpublic note
Note relating to the electronic location of the source identified in the field. The note is written in a form that is not adequate or intended for public display. It may also contain processing information about the file at the location specified.
856 | 1#$awuarchive.wustl.edu$cdecompress with PKUNZIP.exe$d/mirrors2/win3/games$fatmoids.zip$xcannot verify because of transfer difficulty |
$y - Link text
Link text which is used for display in place of the URL in subfield $u. When subfield $y is present, applications should use the contents of subfield $y as the link instead of the content of subfield $u when linking to the destination in subfield $u. The use of the link text is independent of any decision concerning the second indicator value.
856 | 4#$uhttp://susdl.fcla.edu/cgi-bin/cgiwrap/~fdl/fdlcgi?FA00000011 %2Fjpg$yElectronic resource (JPEG) | ||||||||
856 | 4#$uhttp://susdl.fcla.edu/cgi-bin/cgiwrap/~fdl/fdlcgi?FA00000011%2Fpdf$yElectronic resource (PDF) |
$z - Public note
Note relating to the electronic location of the source identified in the field. The note is written in a form that is adequate or intended for public display.
$2 - Access method
Access method when the first indicator position contains value 7 (Method specified in subfield $2). Code from: Electronic Access Methods Code List.
856 | 7#$3b&w film copy neg.$dLCPP003B$f3B44639$2file |
$3 - Materials specified
Part of the item to which the field applies.
856 | 42$3Finding aid$uhttp://lcweb2.loc.gov/ammem/ead/jackson.sgm |
$6 - Linkage
See the description of this subfield in Appendix A: Control Subfields.
$7 - Access status
Code indicating the availability of access to the remote electronic resource the address of which appears in subfield $u. Subfield $7 applies to all subfields $u present in the field.
The remote electronic resource is freely and openly accessible online to everyone, without restriction, login, or payment.
The remote electronic resource is not freely and openly accessible online.
$8 - Field link and sequence number
See the description of this subfield in Appendix A: Control Subfields.
Display Constants - Introductory terms or phrases such as Electronic resource:, Electronic version:, etc. are not carried in the MARC record. They may be system generated as display constants associated with the second indicator value.
Second indicator | Display constant |
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# | Electronic resource: |
0 | Electronic resource: |
1 | Electronic version: |
2 | Related electronic resource: |
8 | [no display constant generated] |
Spacing underscore and tilde in URLs - In February 1994, additional characters in the MARC character set were defined to both accommodate existing bibliographic needs and to align it with the ASCII and ANSEL character sets. Both the spacing underscore and the spacing tilde were added at the time because of the need in directory and file names for electronic resources.
Many systems have implemented these characters, however, for systems that have not implemented the spacing underscore and tilde, the following alternative characters may be used:
%5F for spacing underscore |
%7E for spacing tilde |
Because subfield $g (Electronic name - End of range) was rarely if ever used, it was redefined as Uniform Resource Name in 1997. It was subsequently made obsolete in favor of recording the URN in subfield $u.
Originally defined to contain an indication of whether the file was transferred as binary or ASCII. Redefined to contain type of electronic format.
Prior to 1999, subfield $u was defined as Uniform Resource Locator and was repeatable. It was changed to not repeatable because of ambiguity in determining when the subfield could be repeatable. Subfield $u was changed back to repeatable and renamed Uniform Resource Identifier in 2000 to record both URLs and URNs after subfield $g was made obsolete.