The database Music Online Reference of Alexander Street Press comprises four parts * Classical Scores Library, Volume I - collection of musical prints, manuscripts and up to now unpublished material from the 15th to the 20th century. Please note that Boosey & Hawkes Scores are not included. * Classical Music Reference Library - collection of relevant reference works of approx. 55,000 pages about the history of western classical music from the Middle Ages to the 21st century. * African American Reference Library - comprehensive reference work and collection of rare and up to now unpublished materials about the history of Afro-American music from the beginnings until the 1970s, with a complete coverage of more than 45,000 pages. * The Garland Encyclopedia of World Music Online - comprehensive standard reference work with more than 1,200 elaborate articles about subjects or persons, and approx. 9,200 pages about traditional ethno music worldwide, edited by James Porter and Timothy Rice.

Nature Publishing Group (NPG) is a publisher of high impact scientific and medical information in print and online. NPG publishes journals, online databases, and services across the life, physical, chemical and applied sciences and clinical medicine. The MPG subscription also covers article-processing charges for Max Planck authors in Nature journals. Further details are available on the MPDL website.

Nomos eLibrary provides access to academic books and journals in the subject areas of law, political sciences, economics, media and communication sciences, history, sociology, education and cultural studies, European Union, health sciences. The book selection has been continuously extended through the acquisition of individual eBook packages by MPG libraries. From volume 2022 onwards, access is given to the complete Nomos eBook portfolio. Max Planck researchers can publish their scientific work with Nomos as a print and in parallel as an Open Access eBook in the Nomos eLibrary. Further details are available on the MPDL website.

North American Immigrant Letters, Diaries and Oral Histories includes thousands of authors and approximately 100,000 pages of information, thus providing a unique and personal view of what it meant to immigrate to America and Canada between 1800 and 1950. Composed of contemporaneous letters and diaries, oral histories, interviews, and other personal narratives, the series provides a rich source for scholars in a wide range of disciplines. In selected cases, users will be able to hear the actual audio voices of the immigrants.

Founded in 1916, Optica (formerly the Optical Society of America, OSA) was organized to increase and diffuse the knowledge of optics, pure and applied. One of the Society's major activities is the publication of peer-reviewed journals and books. Though access to current Optica Publishing Group content is no longer licensed, access to the 2007 - 2011 volumes of the journals and proceedings is still available.

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 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.

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.

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.

"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.

RiffReporter is a German news magazine based in Berlin and was founded in 2017. RiffReporter delivers in-depth and thoroughly researched journalistic content on topics such as environment, science, technology, society and global affairs. The cooperatively run journalism portal was awarded the renowned Grimme Online Award in 2018. The MPG subscription covers full text access to all content available on the RiffReporter platform.

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.

SAGE Journals Online provides access to more than 1000 journals with a coverage spanning the humanities, social sciences, and science, technology, and medicine. Max Planck researchers have full text access to a multidisciplinary selection of the full journal collection. In addition, the agreement covers article-processing charges for Max Planck authors in Gold Open Access journals and in hybrid titles in the SAGE Premier package. 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.

The international and interdisciplinary text collection about contemporary and classical theories of society and the social principle compiles writings by Max Weber, Karl Marx, Jürgen Habermas, Robert Merton, George Herbert Mead, Auguste Comte, Jean Baudrillard, Michel Foucault, Saul Howard Becker, Herbert Spencer, Antonio Gramsci, Alexis de Tocqueville, Harriet Martineau, Talcott Parsons, Émile Durkheim, Georg Simmel, Simone de Beauvoir, Pierre Bourdieu, Theodor W. Adorno, etc. Texts frequently appear in their original versions as well as in English translation.