PeerJ is an Open Access, peer-reviewed, scholarly journal. It considers and publishes Research Articles in the Biological and Medical Sciences. It aims for rapid decision making and will publish articles as soon as they are ready. PeerJ operates a 'Lifetime publishing plan' model. Unlike many Open Access publications which charge authors per publication, PeerJ provides low-cost publishing plans to individuals, which gives them lifetime rights to publish with PeerJ for free. The Max Planck Society covers the Enhanced Publication Plan for all Max Planck authors centrally. Further details are available on the MPDL website.

PLOS (Public Library of Science) is a nonprofit publisher and advocacy organization founded to accelerate progress in science and medicine by leading a transformation in research communication. PLOS entered the publishing arena in October 2003 with the launch of PLOS Biology, followed in October 2004 by PLOS Medicine. Today, it publishes a suite of influential Open Access journals across all areas of science and medicine. The Max Planck Society covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

Various dictionaries are available.

The PrimateLit database provides bibliographic access to the scientific literature on nonhuman primates for the research and educational communities. Coverage of the database includes all publication categories (articles, books, abstracts, technical reports, dissertations, book chapters, etc.) and many subject areas (behavior, colony management, ecology, reproduction, field studies, disease models, veterinary science, psychology, physiology, pharmacology, evolution, taxonomy, developmental and molecular biology, genetics and zoogeography).

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".

Das Projekt "Propylaeum – Virtuelle Fachbibliothek Altertumswissenschaften" ist ein Internetportal, das Fachinformationen für den gesamten Bereich der Altertumswissenschaft anbietet, derzeit für die Fächer Ägyptologie, Alte Geschichte, Klassische Archäologie, Klassische Philologie und Vor- und Frühgeschichte. --

PsycCRITIQUES contains full-text reviews of books in psychology and the social sciences, as well as professional videos and popular films from a psychological perspective. Reviews occasionally include comparative or retrospective book reviews. The database also includes all reviews published in the print journal Contemporary Psychology: APA Review of Books between 1956 (Volume 1, Issue 1) and 2004. PsycCRITIQUES ended publication in Fall 2017, the archive is made available by the CCHP in partnership with the APA.

PubMed comprises over 29 million citations for biomedical literature from MEDLINE, life science journals, and online books. PubMed citations and abstracts include the fields of biomedicine and health, covering portions of the life sciences, behavioral sciences, chemical sciences, and bioengineering. PubMed also provides access to additional relevant web sites and links to the other NCBI molecular biology resources. PubMed is a free resource that is developed and maintained by the National Center for Biotechnology Information (NCBI), at the U.S. National Library of Medicine (NLM), located at the National Institutes of Health (NIH).

PubMed comprises over 29 million citations for biomedical literature from MEDLINE, life science journals, and online books. PubMed citations and abstracts include the fields of biomedicine and health, covering portions of the life sciences, behavioral sciences, chemical sciences, and bioengineering. PubMed also provides access to additional relevant web sites and links to the other NCBI molecular biology resources. PubMed is a free resource that is developed and maintained by the National Center for Biotechnology Information (NCBI), at the U.S. National Library of Medicine (NLM), located at the National Institutes of Health (NIH).

A digital archive of life sciences journal literature managed by the National Center for Biotechnology Information (NCBI) at the U.S. National Library of Medicine (NLM).

PubPsych is a free information retrieval system for psychological resources, aiming to enhance the visibility of European and international psychological literature. It offers a comprehensive and balanced selection of resources from a growing number of international databases with a European focus, covering the needs of academic and professional psychologists. PubPsych includes more than 850,000 datasets and offers, where available, full-text linking, links to additional information and link resolving. Databases included: * PSYNDEX * PASCAL * ISOC-Psicología * MEDLINE® * ERIC * NARCIS * NORART * PsychOpen * PsychData

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.

RePEc is a collaborative effort of hundreds of volunteers in 73 countries to enhance the dissemination of research in economics. The heart of the project is a decentralized database of working papers, journal articles and software components. All RePEc material is freely available.

MPG Resource Navigator is a web application to navigate through scientific information resources available to staff and guests of the Max Planck Society. It includes licensed databases, digital collections, and reference works. In addition, recommendable retrieval tools available on the web free of charge are part of the collection. Moreover, almost all Max Planck Institute library catalogs, as well as selected external ones, are accessible from here.

The Royal Society publishes 9 high quality, peer reviewed journals covering the full breadth of the biological, physical and cross-disciplinary science. The Royal Society’s Philosophical Transactions, launched in 1665, was the world’s first scientific journal. It established the fundamental principles of scientific priority and peer review, used throughout scientific publishing ever since. Max Planck researchers have free access to historical journal archives. In addition, the Max Planck Society covers article-processing charges for Max Planck authors publishing in selected journals centrally. Further details are available on the MPDL website.

The RISM database references mostly historical music manuscripts, the majority of them originated before 1800. - The original sources are available from the libraries, music archives, and private collections as indicated in the RISM database. These institutions can often be approached for reproductions. - About 700,000 entries (June 2010). -- Die RISM-Datenbank weist hin auf vor allem historische handschriftliche Noten, die Mehrzahl davon entstanden vor 1800. - Die Originale können in den angegebenen Bibliotheken, Musikarchiven oder Privatsammlungen eingesehen werden. Dort können oft auch Reproduktionen herstellen gelassen werden. - Ca. 700.000 Einträge (Juni 2010).

The SAO/NASA Astrophysics Data System (ADS) is a digital library portal for researchers in astronomy and physics, operated by the Smithsonian Astrophysical Observatory (SAO) under a NASA grant. The ADS maintains three bibliographic databases containing more than 13 million records covering publications in Astronomy and Astrophysics, Physics, and the arXiv e-prints. Abstracts and full-text of major astronomy and physics publications are indexed and searchable through the new ADS modern search form as well as a classic search form.

ScienceOpen is a networking platform for scholars to enhance their research in the open, make an impact, and receive credit for it. The site provides advanced search and discovery functions, combined with post-publication peer review, recommendation, social sharing, and collection-building features. The Max Planck Society covers article-processing charges for ScienceOpen Research and ScienceOpen Poster centrally. Further details are available on the MPDL website.

Freely accessible database with bibliometric information for ranking scientific journals. SCImago uses its own mechanism, based on Google's Pagerank, to rank scientific journals in the fields of natural sciences, engineering, medicine (STM) and social sciences. Based on journal and country-specific indicators recorded in the Scopus scientific database, the citation frequency of publications is analyzed and journals are ranked on this basis.

SciPost is a complete scientific publication portal managed by and for scientists. It is purely online-based, and offers freely, openly, globally and perpetually accessible science (open access). Preprint handling and circulation occurs through the well-established arXiv; the rest of the publication process, from peer refereeing through publication all the way to post-publication commenting, is offered by SciPost. SciPost does not charge individual author fees, the Max Planck Society is a supporting partner of the project.