• CrossRef - The Citation Linking Backbone:

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.

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.

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. The Board of Directors today comprises representatives from AAAS (Science), AIP, APA, Elsevier, IEEE, IOP, Informa UK, Wolters Kluwer Health, Nature, Sage, Springer, Thieme, University of California Press, University of Chicago Press and Wiley-Blackwell.

Among the visitors to the Frankfurt Book Fair in October of 1999 who witnessed the demonstration of the DOI-X project, there were several representatives of the leading scientific, technical, and medical publishers. Recognizing that this prototype of a lookup system based on the Digital Object Identifier (DOI) held the key to a broad-based and efficient journal reference linking system, they took the unusual step of joining together as the non-profit, independent Publishers International Linking Association Inc. (PILA), which was incorporated in January 2000 and CrossRef went live as the first collaborative reference linking service in June 2000.