20.10.2014
Due to an agreement concluded with the Technische Informationsbibliothek der Bundesrepublik Deutschland (TIB) in autumn 2012, PTB as a so-called "data center" can participate in the DOI (Digital Object Identifier) system via the TIB "datacite" association. This enables the long-term-stable addressability, the facilitated detectability and the accessibility of "digital objects" of scientific content in the Internet. The advantage of addressability with DOI names consists in having the permanent validity and resolution of these addresses guaranteed, even if the actual memory location changes. The term "digital object" is, as a rule, not limited in the DOI system; such objects can just as well be pictures, audio and video sequences, notes and maps, data collections and software.
The DOI system is operated by the International DOI Foundation (IDF). In this connection, the standard ISO 26324 "Digital Object Identifier System" is observed due to an agreement between ISO and IDF, in existence since 2010. The DOI names assigned by PTB always begin with "10.7795/". More than 80 of such DOI names have been registered meanwhile for reports, journal articles and conference contributions.
In literature quotes, the DOI names are usually given with the reference "doi: " in front of the DOI name. A URL which is correctly resolved when it is clicked, is given with the addition of "http://dx.doi.org/" in front of the "10".
Example: In the article 
Window function in the English version of Wikipedia, the following literary reference can be found, whereby the quoted DOI name of the respective URL opens directly as a hyperlink:
Albrecht, Hans-Helge (2012). Tailored minimum sidelobe and minimum sidelobe cosine-sum windows. A catalog. doi: 10.7795/110.20121022aa.
Generalsearch sources:All PTB DOI names, search at datacite All PTB DOI names, search at the BASE service of the University of Bielefeld