The CMIF is developed and documented by the TEI Correspondence SIG. The documentation below is an HTML converted version of the original version which is published under a CC BY 4.0 licence in the TEI Correspondence SIG's GitHub repository.
The "Correspondence Metadata Interchange Format" (CMIF) enables scholars to create digital indexes of letters from their scholarly editions and provide them online. The CMIF has been developed by the TEI Correspondence SIG and is a highly reduced and restricted subset of the TEI Guidelines which is based mainly on the TEI element correspDesc
.
The Basis of a digital index of letters according to the CMI format is a TEI-XML file. You can download templates with short descriptions here.
The TEI-XML file contains as many correspDesc
elements as the provider have letters, postcards, etc. in his scholarly edition. A particular correspDesc
element in CMI format is more restrictive and reduced with regard to its vocabulary than the TEI Guidlines generally allow. This enables interchange between the respective TEI documents.
For persons and places in the "correspondence description" (sender, addresssee, senders place etc.) an ID from an authority file should be provided to identify these entities across projects and to use the correspondence metadata in network analysis or web services (e.g. correspSearch). Possible authority files for persons could be:
For places the TEI Correspondence SIG recommends to use the free licensed geographical database GeoNames.
Correspondence Metadata
The following table offers detailed information about the particular parts of a correspDesc
element in the CMI format:
/@key
Number or ID of the letter in the (printed or digital) scholarly edition. To note the number of the letter in @key is especially recommended for printed editions.
Value(s) and NotesE.g. "128
"
/@ref
URL of the letter, if available online. The URL should be an official and permanent link. If different versions of a letter are available, a canonical link should be used.
Value(s) and NotesE.g. "http://edition-humboldt.de/H0002656
"
/@source
Links with the help of an UUID (prefixed by "#") to the bibliographic information (i.e. where the correspondence metadata comes from). Form more information see bibl/@xml:id
below.
E.g. "#c3f497f0-488d-4233-9448-130ba8109bd8
"
/correspAction
Includes the data related to the sending/receiving process of a letter, postcard etc.
Value(s) and NotesOnly the following child elements (no text allowed): persName, orgName, placeName, date
/correspAction/@type
Type of the correspondence action.
Value(s) and NotesAllowed: "sent
", "received
"
/correspAction/persName
Personal name of sender or addressee.
Value(s) and NotesMandatory; if the sender or addressee is unknown please indicate this by the string "Unbekannt
".
/correspAction/persName/@ref
Authority controlled ID of sender or addressee.
Value(s) and NotesStrongly recommended, if available. Possible authority files: VIAF, GND, LC, BNF and NDL (see above).
/correspAction/orgName
Name of institution, company etc.
Value(s) and NotesOptional, if PersName
is not applicable.
/correspAction/placeName
Name of the place a letter was sent from or where it is being sent to.
Value(s) and NotesIf available.
/correspAction/placeName/@ref
Authority controlled ID of the place a letter was sent from or where it is being sent to.
Value(s) and NotesStrongly recommended, if available. Possible authority files: GeoNames (see above).
/correspAction/date
Machine-readable date of when the letter was sent or received.
Value(s) and NotesIf available. The CMIF supports the attributes @when
, @from
, @to
, @notBefore
und @notAfter
. To facilitate the interchange, the CMIF supports (unlike the TEI Guidelines) only the following date formats:
The correspDesc
elements are noted inside TEI/teiHeader/profileDesc
- as described in the TEI Guidelines.
Besides the correspondence metadata, the provider have to include some information about the CMIF file and the digital index of letters itself in the teiHeader/fileDesc
element. All elements there are mandatory if not stated otherwise.
//titleStmt/title
Title of the digital index of letters.
Value(s) and NotesFree text field.
//titleStmt/editor
Contact person concerning the digital index of letters.
Value(s) and NotesIf available with an e-mail address in editor/email
.
//publicationStmt/publisher
Originator of the letter metadata as defined in the Creative Commons Licence CC-BY 4.0.
Value(s) and NotesFree text field.
//publicationStmt/availability/licence
Licence statement.
Value(s) and NotesMandatory: "This file is licensed under the terms of the Creative Commons License CC-BY 4.0
".
//publicationStmt/availability/licence/@target
URL of the licence.
Value(s) and NotesMandatory: "https://creativecommons.org/licenses/by/4.0/
".
//publicationStmt/date/@when
Timestamp of the last update of this file.
Value(s) and NotesFormat: xsd:dateTime.
//publicationStmt/idno
URL of this digital index of letters.
Value(s) and NotesThe URL serves as a unique identifier for the CMIF file and ensures that the file can always traced back to their origin.
//publicationStmt/idno/@type
Type of the above mentioned identifier.
Value(s) and NotesMandatory: "URL
" .
//sourceDesc/bibl
Bibliographic information about the scholarly edition from which the correspondence metadata is derived from.
Value(s) and NotesNo specifications.
//sourceDesc/bibl/@xml:id
Technical ID of the bibl element, i.e. the bibliographic information. An UUID have to be used. The correspDesc items have to be referenced by this UUID (see above @source).
Value(s) and NotesE.g. "#c3f497f0-488d-4233-9448-130ba8109bd8
". UUID can easily be generated by many online tools. If the CMIF is created via a script (as common in digital scholarly editions), it is recommended to use a "static" UUID, i.e. which is not re-generated every time the CMIF data is updated.
//sourceDesc/bibl/@type
Type of scholarly edition.
Value(s) and NotesThe following values are allowed: "print
", "online
".
For more information see the FAQ section.
You can find further examples of the CMI format on the GitHub repository of the TEI Correspondence SIG.
A blog article on digiversity discusses the further development of the CMI format.