CrossRef, founded in 2000, is a not-for-profit organization that provides persistent digital object identifiers (DOIs) for scholarly content, enabling features like hyperlinking references and tracking citations. With over 76 million DOIs registered for various types of scholarly works, it collaborates with the International DOI Foundation and other registration agencies to ensure the persistence and interoperability of DOIs. The document outlines registration processes, metadata requirements, DOI usage guidelines, and ways to seek support from CrossRef.

1. Introduction to Crossref
Patricia Feeney
Product Support Manager

2. Founded in 2000
A not-for-profit trade association of global
scholarly publishers
Members from over 80 countries
5770 international publishers & societies
76+ million DOIs registered

3. Why do publishers join CrossRef?
 To get persistent identifiers for their
content
 To drive more traffic to their content
 To turn references into hyperlinks
 To pull in cited-by links (who cites this?)
 Participate in other collaborative services
and in (CrossCheck, CrossMark)

4. DOI = Digital Object Identifier
 Uniquely identifies a digital object
 Solves link rot (broken links)

5. 76,288,012 Crossref DOIs!
* figures, tables, supplemental materials
Also: Standards, Working Papers, Dissertations, Datasets
CrossRef Status Page
Type # titles #DOIs % of total
Journals 39,870 57,434,631 77%
Books 618,900 9,537,792 13%
Proceedings 44,148 4,061,186 5%
Components* 1,974,120 2%

6. International DOI Foundation (IDF):
oversees the central DOI system, promote
DOI as a standard, and provides an
organizational infrastructure that ensures
persistence and interoperability.
Corporation for National Research
Initiatives (CNRI): they (among other things)
are responsible for the Handle system, which
is the technology that causes DOIs to resolve.
Registration Agencies (RAs): Register
DOIs on behalf of other organizations.
CrossRef is a RA.

8. Deposit DOIs and metadata
Basic citation metadata:
author (s), journal title, article title, volume, issue,
publication date, book title, chapter title, page numbers,
article IDs, internal identifiers, ISSN, ISBN…
Optional (but recommended):
Funding information, ORCIDs, references (to support cited-
by linking), CrossMark metadata, text and data mining
license information

9. http://dx.doi.org/
DOI directory
10.1666/
DOI prefix
09-114.1
DOI suffix

10. http://dx.doi.org/10.1666/09-114.1<- DOI

11. Prefix:
 Assigned to members
 Format is 10.XXXX (or
10.XXXXX)
 Identifies who initially created
the DOI
 Prefix does not identify the
current owner of the DOI
Suffix:
 Unique within a prefix – a DOI can
only be assigned to one item
 Consistent
 Logical
 Easily documented
 Readily implemented
 case insensitive
http://dx.doi.org/10.1006/jmbi.1995.0238
http://dx.doi.org/
DOI directory
10.1006/
DOI prefix
jmbi.1995.0238
DOI suffix
More info: creating a suffix

12. The vast majority of
transactions are made via a
machine interface
Public interface:
Web deposit form:
http://www.crossref.org/webDeposit/
System interface:
http://doi.crossref.org
HTTP
More info: Deposit Basics
Deposit interfaces

13. Publishing and displaying DOIs
Display CrossRef DOIs as a URL
Include CrossRef DOIs on response pages
(required), TOCs, abstracts, PDFs, citation
downloads, metadata feeds, social network
links
Do not publicize DOIs until links are live

14. Display DOIs
Response page must include:
 bibliographic information about the item
 means to access full text
 the DOI

15. Outbound Reference Linking

16. DOI guidelines
http://www.crossref.org/02publishers/doi_display_guidelines.html
Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin
structure in G0 cells. Mol. Cell. 12:255–260, http://dx.doi.org/10.1016/S1097-
2765(03)00225-9
Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin
structure in G0 cells. Mol. Cell. 12:255–260, http://doi.org/bm6
Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin
structure in G0 cells. Mol. Cell. 12:255–260 http://dx.doi.org/10.1016/S1097-
2765(03)00225-9
Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin
structure in G0 cells. Mol. Cell. 12:255–260
Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin
structure in G0 cells. Mol. Cell. 12:255–260, CrossRef.
Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin
structure in G0 cells. Mol. Cell. 12:255–260, Article.

18. Public interfaces:
SimpleText Query
CrossRef Metadata Search
http://doi.crossref.org
Machine interfaces:
HTTP POST or GET
OpenURL
OAI-PMH (for CMS
subscribers)
More info: How Querying Works
Query interfaces

19. Update metadata and URLs
Easy URL update:
H:email=pfeeney@crossref.org;fromPrefix=10.5555;toPrefix=10.5555
10.5555/doi1 http://www.yoururl.com/journal/art1
10.5555/doi2 http://www.yoururl.com/journal/art2
10.5555/doi2 http://www.yoururl.com/journal/art12
 There is no charge for updating your DOIs – we encourage you to
update them as often as needed.
 Acquire a title from a Crossref member? DO NOT create new DOIs
for existing content.

20. Resolve all conflicts
Conflict: two (or more) DOIs share the same
metadata, suggesting two DOIs are assigned to a
single item.

21. Recurring reports:
 Resolution Report (email)
As-needed reports:
 Conflict
 DOI Error Report (email)
 Schematron Report (email)
Always available:
 Depositor Report
 Status Report
 Go-live report
 Title list
Tools
 XML Parser
 Test system: http://test.crossref.org
 Deposit Harvester
Reports!

22. Resolution Report (emailed monthly)
More info: Resolution Report

23. Make plans for long-term archiving
CLOCKSS: http://clockss.org
Koninklijke Bibliotheek / National Library of the
Netherlands: http://www.kb.nl/
Portico: http://www.portico.org

24. Pay bills and keep in touch
Billing:
 Annual membership feel billed annually, sent out in
December
 Deposit fees billed quarterly*
Keep in touch!
Send any contact changes to info@crossref.org

25. Where to find help:
 Help docs: http://help.crossref.org
 support@crossref.org or visit http://support.crossref.org
 Webinars
Staying up to date:
Twitter:
@CrossrefOrg: general news and updates
@CrossrefSupport: technical updates (outages, schema
changes)
Crossref Labs: new and experimental tools and initiatives
Crossref.org

26. Questions?
Technical support: support@crossref.org
Membership support: info@crossref.org