BASE is a multidisciplinary search engine for scholarly internet resources which have been harvested from several hundred scientific repositories. Some of the indexed resources in BASE are subject to license, while most material is free available ("open access").

The Staatsbibliothek zu Berlin - Preußischer Kulturbesitz (Berlin State Library - Prussian Cultural Heritage) acquires texts from all fields of knowledge in all languages, in every available form, from all epochs and all countries of the world - providing the materials are of interest for academic and research purposes. Current holdings and collections include printed works from many centuries, manuscripts, music autographs, maps, globes, atlases, newspapers and periodicals, various microformed materials, an increasing number of digitally presented texts as well as extensive databases.

Copac exposes rare and unique research material by bringing together the catalogues of c.90 major UK and Irish libraries. In a single search you can discover the holdings of the UK’s national libraries (including the British Library), many University libraries, and specialist research libraries.

Walter De Gruyter publishes a wide variety of content covering humanities, medicine, the sciences and law. The "De Gruyter Online" platform provides access to title information and the electronic content for De Gruyter journals and books under one roof. Users from the MPG have access to following products: * De Gruyter Journals and Yearbooks - current content of selected serial titles available on the platform (last 13 volumes) * De Gruyter Journal Archive - backfile content of 150 titles * De Gruyter Online / Research Now E-Journal Archive - about 50 journals focusing on research in economics, formerly published by Berkeley Electronic Press until 2022 * De Gruyter eBooks - a collection of purchased e-books which is continuously extended by single e-book acquisitions by MPG libraries

The Deposit Once of the Technische Universität Berlin makes qualified scientific text documents and research data of members of the TU Berlin available online. The repository is committed to the principles of Open Access and includes parallel publications from peer-reviewed publishers (post-prints) as well as dissertations, monographs, conference proceedings, collections and other scientific treatises.

The catalog comprises the holdings of the locations Leipzig since 1913, Frankfurt am Main since 1945, the holdings of the Deutsches Musikarchiv since 1976, and archival papers of the Deutsches Exilarchiv 1933-1945 since 2005. The catalog covers monographs, journals, maps and atlases, music and sound storage media, and dissertations published in Germany since 1913 (in print or electronically), in addition, translations from German into other languages and foreign-language works related to Germanic culture (since 1941). -- Der Katalog umfasst die Bestände der Standorte Leipzig seit 1913, Frankfurt am Main seit 1945, die Bestände des Deutschen Musikarchivs seit 1976 und die Archivalien des Deutschen Exilarchivs 1933-1945 seit 2005. Der Katalog beinhaltet in Deutschland seit 1913 erschienene Monografien, Zeitschriften, Karten und Atlanten, Musikalien und Tonträger, Dissertationen und Habilitationsschriften in gedruckter oder elektronischer Form, außerdem Übersetzungen aus dem Deutschen in andere Sprachen und fremdsprachige Germanica (seit 1941).

ProQuest Dissertations and Theses Global is the world's most comprehensive collection of dissertations and theses, covering materials back to the first U.S. dissertation, accepted in 1861, as well as to European dissertations from the 17th century. The database is the official dissertations repository for the Library of Congress, with 5.5 million bibliographic citations, 3 million full texts, 4,100 contributing institutions worldwide and 250,000 works added annually. Full-text coverage spans from 1743 to the present, with citation coverage dating back to 1637.

The Document and Publication Server of the Humboldt-Universität zu Berlin is a service of the university library and the computer and media services. It offers the organisational and technical framework to all members of HU Berlin for publishing scientific documents digitally. Documents that are stored include single publications and publication series, collections, conference papers, research reports, journals (e-journals), theses and dissertations, master theses and seminar papers.

The EZB is a huge directory of electronic journals which mirrors the central Max Planck Society subscriptions as well as the local licensing situation of the institutes. Access rights to the contents of the individual journals are indicated with "traffic lights". Entries are searchable on journal level.

Throughout Europe, national patent offices and the European Patent Office (EPO) offer free patent information on the Internet Patents reveal solutions to technical problems, and they represent an inexhaustable source of information: more than 80 percent of man's technical knowledge is described in patent literature. From the middle of 1998 onwards, esp@cenet users have been able to access the bibliographic data of all patents published in the preceding two years by any member state of the European Patent Organisation, as well as by the European Patent Office and the World Intellectual Property Organization (WIPO). In addition, full-page facsimile images of documents are also retrievable to facilitate more detailed analysis of these documents. The data for this particular service is stored at the relevant national office.

GBV is the Common Library Network of the German Federal States Bremen, Hamburg, Mecklenburg-Vorpommern, Niedersachsen, Sachsen-Anhalt, Schleswig-Holstein and Thüringen. The head office of the GBV (VZG) is situated in Göttingen. The GBV has established a virtual library in form of the GBV Union Catalogue (GVK) combining the resources of all participating libraries and making them easily accessible to the public.

Google Book Search is a service from Google that searches the full text of books that Google scans, converts to text using optical character recognition, and stores in its digital database.

The union catalog lists the holdings of all scientific libraries in Hessen and Rheinhessen. Inter-library loan requests may be submitted.

This database of the European Union (EU) contains the complete EU related terminology in all 24 official languages of the EU. -- Diese Datenbank der Europäischen Union (EU) enthält die gesamte EU-bezogene Terminologie in allen 24 EU-Amtssprachen.

Book reviews are an important element in the academic discussions. They are a tool for quality measurement with respect to the amount of publications published annually and give an indication of the importance of a published work. IBR contains over 1,16 million entries on book reviews from the years 1985ff. The database is international and interdisciplinary, over 560.000 reviews have been published in approx. 6,723 academic journals mainly in the Humanities and Social Sciences. ---- Rezensionen sind ein wichtiges Element der wissenschaftlichen Diskussion. Sie sind ein Qualitätsfilter in der jährlichen Publikationsflut und sind mitbestimmend für den Stellenwert eines Werkes. Die IBR umfasst über 1,16 Mio. Nachweise von Rezensionen aus den Jahren 1985ff. Sie weist ca. 6.723 interdisziplinäre, internationale, vornehmlich die Geistes- und Sozialwissenschaften berücksichtigende Rezensionen in wissenschaftlichen Zeitschriften zu 560.000 rezensierten Werken nach.Verbindung zum Volltext der Rezension via SFX

The Karlsruhe Virtual Catalogue (KVK) is a meta search engine which allows you to simultaneously access selected library and book trade catalogs worldwide. Altogether, these resources contain hundreds of millions of books, magazines and other media.

The KOBV-Index is a central database that is maintained and regularly updated at KOBV-Zentrale. Der KOBV-Index ist eine zentrale Datenbank, die in der KOBV-Zentrale gepflegt und regelmäßig aktualisiert wird.

Various dictionaries are available (incl. Duden).

The Max Planck e-Book Index provides holdings of electronic books licensed for users in the Max Planck Society.

The Max Planck Journal Index provides holdings of a great range of printed journals available within the Max Planck Society. Besides, it contains metadata of electronic journals as loaded from the EZB. The database is updated regularly from the ZDB (twice a year) and the EZB (monthly).

MPG.PuRe is the publication repository of the Max Planck Society. It contains bibliographic data and numerous fulltexts of the publications of its researchers. The repository is based on PubMan, a publication repository software developed by the Max Planck Digital Library. PuRe was introduced in the MPG in May 2009 and replaced the former institutional repository eDoc.

A collaborative effort of the Networked Digital Library of Theses and Dissertations (NDLTD), OCLC, VTLS, and Scirus, the NDLTD Union Catalog contains more than one million records of electronic theses and dissertations. For students and researchers, the Union Catalog makes individual collections of NDLTD member institutions and consortia appear as one seamless digital library of electronic theses and dissertations.

In OLC you have access more than 25 million articles from over 20,000 scientific periodicals beginning with the year of publication 1993. The Online Contents records are supplied by Swets and are updated daily.

Various dictionaries are available.

Project Gutenberg is a volunteer effort to digitize and archive cultural works. Founded in 1971 by Michael Hart, it is the oldest digital library. Project Gutenberg's mission is "To encourage the creation and distribution of eBooks".

Refubium is a service of the university library of the Freie Universität Berlin. As an institutional repository it collects documents, dissertations, postdoctoral theses, and research data.

The BSZ develops and maintains the SWB database in cooperation with 1,200 libraries in Baden-Württemberg, Pfalz, Saarland and Sachsen. The online catalog offers bibliographic data free of charge: Monographs, periodicals, articles, loose-leaf collections, off-prints, conference proceedings, university publications, reviews, abstracts, tables of contents, maps, music, audiovisual material, microforms, electronic resources (data media), online resources; scientific and popular literature from all subjects and in all languages from the 15th century to the present; scientific literature (according to the DFG special subject fields programme) from theology, ancient orient, art, music, archeology, law and criminology;

The ZDB is the world’s largest specialized database for serial titles (journals, annuals, newspapers etc., incl. e-journals). The ZDB contains more than 1 million bibliographic records of serials from the 16th century onwards, from all countries, in all languages, held in 4000 German (and some foreign) libraries, with holdings information. It does not index individual journal articles.