1. There is no thing worse than treachery in the world, be killer but don’t be a treacherous. Abdalsamad Keramatfar, Scientometrics section, SID

3. At the beginning of 2000, the world's leading scholarly publishers joined to form the non-profit, independent organization, Publishers International Linking Association, Inc. (PILA), which operates CrossRef. Abdalsamad Keramatfar, Scientometrics section, SID

4. A not-for-profit network founded on publisher collaboration, with a mandate to make reference linking throughout online scholarly literature efficient and reliable and develop other services that are best achieved through collaboration. CrossRef is a DOI Registration Agency and is committed to long term sustainability.DOI Abdalsamad Keramatfar, Scientometrics section, SID

5. A unique alphanumeric string assigned to a object – in this case, an electronic journal article or a book chapter. In the CrossRef system, each DOI is associated with a set of basic metadata and a URL pointer to the full text, so that it uniquely identifies the content item and provides a persistent link to its location on the internet. Abdalsamad Keramatfar, Scientometrics section, SID

6. A product for sale An article database A direct-to-end-user service A search interface A broker of full-text content Made up of just big commercial publishers Abdalsamad Keramatfar, Scientometrics section, SID

7. CrossRef is a not-for-profit membership association whose mission is to enable easy identification and use of trustworthy electronic content by promoting the cooperative development and application of a sustainable infrastructure. Abdalsamad Keramatfar, Scientometrics section, SID

8. CrossRef's general purpose is to promote the development and cooperative use of new and innovative technologies to speed and facilitate scholarly research. CrossRef's specific mandate is to be the citation linking backbone for all scholarly information in electronic form. CrossRef is a collaborative reference linking service that functions as a sort of digital switchboard. It holds no full text content, but rather effects linkages through CrossRef Digital Object Identifiers (CrossRef DOI), which are tagged to article metadata supplied by the participating publishers. The end result is an efficient, scalable linking system through which a researcher can click on a reference citation in a journal and access the cited article. Abdalsamad Keramatfar, Scientometrics section, SID

9. Scholarly publishers developed CrossRef. The initial service was based on a prototype developed by John Wiley & Sons and Academic Press, in cooperation with the International DOI Foundation (IDF). It built on the DOI-X project led by the IDF, Association of American Publishers (AAP) and the Corporation for National Research Initiatives (CNRI).IDF(AAP)(CNRI). Abdalsamad Keramatfar, Scientometrics section, SID

10. No broken links: Because a DOI link is a persistent link, unlike a URL, publishers and others who use CrossRef create reliable, persistent links in citations and database records. A single agreement with CrossRef serves as a linking agreement with all participating publishers. Avoid having to sign numerous bilateral linking agreements with publishers. Add value to your electronic publications: Readers have come to expect online material to contain outbound links to cited sources. At the same time, CrossRef linking will augment the accessibility of your content through inbound links. Abdalsamad Keramatfar, Scientometrics section, SID

11. CrossRef DOI links must—as an obligation of CrossRef membership—be included in members’ online journal citation lists. Whenever possible CrossRef DOI links should also be included in citations in other types of scholarly content. They can be displayed in several ways, depending on the publisher’s preference and publication style. CrossRef recommends the following options. Abdalsamad Keramatfar, Scientometrics section, SID

12. Use the CrossRef DOI URL as the permanent link. Example 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)00225-9http://dx.doi.org/10.1016/S1097- 2765(03)00225-9 Abdalsamad Keramatfar, Scientometrics section, SID

13. Use a ShortDOI as the permanent link. Short doi service: http://shortdoi.org/ Abdalsamad Keramatfar, Scientometrics section, SID

14. Display the CrossRef linking graphic next to the permanent DOI link. Example Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin structure in G0 cells. Mol. Cell. 12:255–260 Abdalsamad Keramatfar, Scientometrics section, SID

15. Display the text “CrossRef” with a permanent DOI link behind the text. Example Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin structure in G0 cells. Mol. Cell. 12:255–260, CrossRef.CrossRef Abdalsamad Keramatfar, Scientometrics section, SID

16. Display the words “Full Text” or “Article” or something similar with the permanent DOI link behind the text. Example Ghosh, M.K., M.L. Harter. 2003. A viral mechanism for remodeling chromatin structure in G0 cells. Mol. Cell. 12:255–260, Article.Article Abdalsamad Keramatfar, Scientometrics section, SID

17.  Publishers of electronic scholarly content join as members and are assigned a DOI prefix.  For each content item a publisher wishes to register in the system, it creates a unique DOI (incorporating the assigned prefix) and tags it to the article’s metadata and the URL where the article resides.  The publisher submits the record to the CrossRef metadata database (MDDB) in a strict XML-based DTD format.  CrossRef then registers each article DOI and URL in a central DOI directory. Abdalsamad Keramatfar, Scientometrics section, SID

18.  In a separate process, the publisher also submits the citations contained in each deposited article to the Reference Resolver, the front-end component of the MDDB that allows for the retrieval of DOIs. This way, the publisher can, as part of its electronic production process, add outbound links to any of an article’s citations that point to content already registered in the CrossRef system. Abdalsamad Keramatfar, Scientometrics section, SID

19. The DOI Resolution system is run by CNRI on behalf of the IDF. When a user clicks on a link containing the DOI, the DOI Resolution system directs the user to the URL submitted by the publisher. The process of resolving a DOI happens outside of CrossRef.CNRIIDF Abdalsamad Keramatfar, Scientometrics section, SID

20. CrossRef does not aggregate full-text content. Rather, it uses a system of “distributed aggregation” whereby full-text content is linked through a database consisting of minimal publisher metadata. Each record in the database is essentially a triplet: {metadata + URL+DOI}. Abdalsamad Keramatfar, Scientometrics section, SID

21. Intermediaries, such as secondary publishers, aggregators, and abstracting and indexing services, participate as CrossRef Affiliates. Affiliates use CrossRef for DOI retrieval, to link their own records to the location of primary publisher content.CrossRef Affiliates Abdalsamad Keramatfar, Scientometrics section, SID

22. A researcher clicking on a CrossRef link will be automatically connected to a page on the publisher's website showing a full bibliographical citation of the article, and, in most cases, the abstract as well. Subscribers are generally authenticated for full text access, and non-subscribed users presented with other options for access (such as subscription, document delivery, or pay-per-view). Researchers in library environments may find that CrossRef links redirect to local holdings. Abdalsamad Keramatfar, Scientometrics section, SID

23. Members must do the following in order to participate in the reference linking system: Join CrossRef. It is not necessary to get a DOI Prefix before joining CrossRef. The fee for the DOI Prefix is included in the CrossRef Membership Fees and there is no need to pay a separate fee to the International DOI Foundation. After joining CrossRef, information on getting a DOI Prefix and assigning DOIs will be provided. Assign DOIs journal articles. It is not necessary to register DOIs separately with the International DOI Foundation since this will be done automatically as part of the CrossRef metadata submission process. Adhere to the requirements of the DOI system. The publisher must submit a minimal set of metadata about each article as XML compliant with the CrossRef deposit schema: journal title, ISSN, first author, year, volume and issue, page numbers and DOIs and URLs. A publisher may choose to submit additional metadata, at its option. Publishers who have a small volume of records and who cannot easily supply XML can use the Web Deposit Form http://www.crossref.org/webDeposit/ to deposit their metadata.The DOI/URL will be registered with the International DOI Foundation in the DOI Directory.CrossRef deposit schemahttp://www.crossref.org/webDeposit/ Abdalsamad Keramatfar, Scientometrics section, SID

24. حافظ بدید نکبت این جامعه که گفت : « باید برون کشید از این ورطه رخت خویش » Abdalsamad Keramatfar, Scientometrics section, SID