Ganjoor
Classic Persian poetry works including access to related manuscripts, recitations and music tracks

Books.
Google Books API is a free Books API that requires OAuth authentication, is served over HTTPS and has unconfirmed CORS support.
Learn to use the Google Books API so your app can search text and retrieve book information.
Details from developers.google.com.

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The Google Books API is provided by Google Books APIs (developers.google.com). Learn to use the Google Books API so your app can search text and retrieve book information.
Yes. The Google Books API is listed in the Books category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Google Books API uses OAuth authentication, so you need to register for credentials before making requests.
CORS support for the Google Books API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Google Books API is served over HTTPS, so it's safe to use in production.