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.

Frontiers is a community-oriented open-access academic publisher and research network. It was launched in 2007 by scientists from the Swiss Federal Institute of Technology in Lausanne and aims to provide better tools and services to researchers in the Internet age. Since then, Frontiers has become one of the fastest-growing open-access scholarly publishers: over 400,000 high-quality, peer-reviewed articles have been published in about 200 community-driven journals across more than 300 specialty niches in science, medicine and technology. The Max Planck Society covers article-processing charges for Max Planck authors 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.