arXiv is an e-print service in the fields of physics, mathematics, computer science, quantitative biology, quantitative finance, statistics, electrical engineering and systems science, and economics. It provides access to more the 1.3 million e-prints. The Max Planck Society is a member institution of arXiv.

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

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).

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.

Zenodo is an open data repository, developed and operated by CERN. It is an catch-all repository, that welcomes research from all over the world, and from every discipline. Zenodo does not impose any requirements on format, size, access restrictions or licence. A digital object identifier (DOI) is automatically assigned to all Zenodo files and it is integrated into reporting for research funded by the European Commission.