The Online Contents service of the Special Subject Collection Political Science and Peace Research is part of the Online Contents database. It offers access to tables of contents of more than 870 journals relevant for study and research. New journals were added until December 2013 by the Special Subject Collection. Thus the database contains approximately 1.478,600 records of journal articles and reviews.

The OSF Preprints search combines records from various preprint repositories, including arXiv, bioRxiv, Cogprints, PeerJ, PsyArXiv, RePEc and SocArXiv.

Developed cooperatively with scholars and librarians worldwide, Oxford Bibliographies offers exclusive, authoritative research guides across a variety of subject areas. Combining the best features of an annotated bibliography and a high-level encyclopedia, this cutting-edge resource directs researchers to the best available scholarship across a wide variety of subjects.

Oxford Constitutions of the World (OCW) contains fully-translated English-language versions of all the world's constitutions (both national and sub-national), accompanied by individual jurisdictional commentaries, and supplementary materials, including foundation documents, historical versions of constitutions, and amendment Acts/Laws. The Max Planck Encyclopedia of Comparative Constitutional Law (MPECCOL) is a comprehensive online resource containing analytical comparative articles offering a global overview of constitutional law. Subscribers also benefit from access to the Oxford Law Citator, one of the most powerful tools available for legal research, enabling onward research and ease of access to key materials.

Oxford Handbooks Online is a collection of handbooks in 17 subject areas, bringing together the world's leading scholars to write review essays that evaluate the current thinking on a field or topic, and make an original argument about the future direction of the debate. For the first time, all Handbooks are available online as well is in print across the subject areas. Monthly updates introduce articles in advance of print publication and beyond the book, online-only content ensures the most current, authoritative coverage anywhere.

Including Oxford Scholarship Online (OSO), the University Press Scholarship Online (UPSO) publishes new books every month from an ever-growing roster of contributing presses, each adding to the variety of subjects covered on the platform. The MPG purchased the volumes 2003-2013/2014 of 16 OSO subject collections. This selection is continuously extended by single e-book acquisitions by MPG libraries.

Periodicals Archive Online is a major archive that makes the backfiles of scholarly periodicals in the arts, humanities and social sciences available electronically, providing access to the searchable full text of hundreds of titles. The database spans more than two centuries of content, 37 key subject areas, and multiple languages.

This historic journal index enables the simultaneous search in millions of citations for articles published in the arts, humanities and social sciences, across more than 300 years. It enables researchers quickly and comprehensively to identify articles relevant to their field of study and reduces what could take years of research to a matter of minutes. Journals indexed span 37 key subject areas and multiple languages.

The "JPS Journals" platform provides access to the academic journals published by the Physical Society of Japan (JPS). These journals cover the subject area from condensed matter physics to particle physics.

Project MUSE is a leading provider of digital humanities and social science content for the scholarly community. Since 1995 the MUSE journal collections cover full-text versions of scholarly journals from many of the world's leading university presses and scholarly societies, with over 120 publishers currently participating.

PsycARTICLES comprises journals published by the American Psychological Association, the APA Educational Publishing Foundation, the Canadian Psychological Association, and Hogrefe Publishing Group, from 1894 onwards.

The PsycINFO databases cover the professional and academic literature in psychology and related disciplines including medicine, psychiatry, nursing, sociology, education, pharmacology, physiology, linguistics, and other areas. Coverage is worldwide, and includes references and abstracts to over 1300 journals and to dissertations in more than 30 languages, and to book chapters and books in the English language. Over 50,000 references are added annually. Popular literature is excluded.

The PsyJOURNALS collection is a diverse portfolio of highly-regarded, peer-reviewed journals in German and English languages published by Hogrefe and by Hans Huber that cover a wide range of areas within psychology and psychiatry. Max Planck researchers have full text access to 31 journals from 2015 onwards, with a two-year moving wall.

"Psyndex - Literature & Audiovisual Media" contains records on psychology from researchers in Germany, Austria, and Switzerland. Compiled by the German Center for Documentation and Information in Psychology at the University of Trier (ZPID), this database covers German and English journal articles, books, chapters, reports, dissertations as well as audiovisual media. The database is bilingual: titles and descriptors are in German and English. German publications are abstracted in German; English publications in English. The database is indexed with the Thesaurus of Psychological Index Terms by permission of the American Psychological Association. A bilingual thesaurus is included with the database.

"Psyndex - Tests" contains records on psychology from researchers in Germany, Austria, and Switzerland. Compiled by the Leibniz Institute for Psychology Information (ZPID), this database covers about 5,000 extensive descriptions of psychological and educational tests used in the German-speaking countries. "Psyndex - Tests" is bilingual: titles and descriptors are in German and English. German publications are abstracted in German; English publications in English. The database also include theoretical background, testing procedures, test construction, reliability, validity, fields of application, research and other selected literature, a comprehensive discussion, and test reviews. "Psyndex - Tests" is indexed with the Thesaurus of Psychological Index Terms by permission of the American Psychological Association (APA). A bilingual thesaurus is included with the database.

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.

SciELO (Scientific Electronic Library Online) is a program of the Sao Paulo Research Foundation for the cooperative publishing of open access journals on the internet. Content includes regional journals from Latin American and the Caribbean as well as titles from Spain, Portugal and South Africa. The index covers approximately 650 titles (over 350 adding content to journals already covered in the Web of Science) and contains several million cited references.

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.

SocArXiv, open archive of the social sciences, provides a free, non-profit, open access platform for social scientists to upload working papers, preprints, and published papers, with the option to link data and code. SocArXiv is dedicated to opening up social science, to reach more people more effectively, to improve research, and build the future of scholarly communication.

SocINDEX is the world's most comprehensive and highest quality sociology research database. Subject headings from a 15,000 term sociology-specific thesaurus designed by expert lexicographers and extensive indexing for books, monographs, conference papers and other sources is included. Searchable cited references are also provided.