Alternativer til Unpaywall til Opera med open source-licens

• Opera
  Alle platforme Windows Mac Linux Chrome OS Android iPhone Apple Watch iPad Android Tablet Windows S Web Self-Hosted Software as a Service (SaaS) Firefox Opera Safari Chromium Vivaldi Browser BSD Chrome Microsoft Edge Yandex.Browser Maxthon Cloudron
• Open Source-licens
  Enhver licens Gratis licens Open Source-licens Kommerciel licens