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The LibraryODERSA publishing house
An ODERSA resource · Knowledge programmeA book only goes online once it is whole and read by someone else.

Sources and references

This site makes claims about what exists elsewhere. Here is where to check them, and when they were checked.

Why this page exists

The home page of this site states that complete openly licensed textbooks already exist, in English as well as in French and Spanish, and that the real gap lies elsewhere. A claim of that kind commits the house: it can be checked, or it does not get written.

The references below were opened online, one by one, on the date given. They are the projects themselves and the official texts, not articles summarising them. Where something could not be verified, it is not written on this site, and this page says so at the end.

A row of heavy leather-bound volumes seen at an angle: the text blocks have warped, the leather is crazed, and the paper labels are worn.
Volumes whose paper has warped and whose leather is crazing. A book printed once eventually decays; a book you are allowed to reprint does not. It is the best argument for an open licence, and it has nothing to do with anything digital.Credit

The open textbooks that already exist

The ones this house points to when it says it has no reason to redo that work. The licences given are the ones those projects state themselves.

  1. Sesamath, mathematics textbooks and workbooks from primary to upper secondary, with their editable filesSesamath association, France · GNU FDL and CC BY-SA · checked on August 6, 2026manuel.sesamath.net
  2. Lelivrescolaire.fr, collaborative textbooks written by teachers, across all subjectsFrance · CC BY-NC-SA · checked on August 6, 2026www.lelivrescolaire.fr
  3. Apuntes Marea Verde, textbooks in several subjects written by state-school teachers, printable and editableSpain · CC BY-NC-SA · checked on August 6, 2026www.apuntesmareaverde.org.es
  4. Open Textbook Library, a catalogue of complete open textbooks with published admission criteriaUniversity of Minnesota · open licences, no-derivatives clause excluded · checked on August 6, 2026open.umn.edu/opentextbooks
  5. OpenStax, peer-reviewed university textbooks, in English and SpanishRice University · CC BY 4.0 for most of the catalogue · checked on August 6, 2026openstax.org
  6. Siyavula, complete school textbooks in mathematics and science, unbranded versionsSouth Africa · CC BY 3.0 for the unbranded versions · checked on August 6, 2026www.siyavula.com/read

Free of charge, but not free to reuse

State textbooks that download without payment and that nobody is allowed to reprint. That is the gap this house comes to fill, and it can be read in the usage terms of those sites.

  1. Copyright policy of NCERT, Indian school textbooks: downloading allowed, republishing forbiddenNational Council of Educational Research and Training, India · all rights reserved · checked on August 6, 2026osre.ncert.gov.in/copyright-policy
  2. Free school textbooks of Bangladesh, distributed by the stateNational Curriculum and Textbook Board, Bangladesh · no licence stated · checked on August 6, 2026nctb.gov.bd
  3. Open textbooks, the notion and the state of the art in ArabicArabic Wikipedia · CC BY-SA · checked on August 6, 2026ar.wikipedia.org/wiki/%D9%83%D8%AA%D8%A7%D8%A8_%D9%85%D8%AF%D8%B1%D8%B3%D9%8A_%D9%85%D9%81%D8%AA%D9%88%D8%AD

The texts that frame this site

The licences and standards this house applies, at their official address.

  1. Creative Commons Attribution 4.0 International licence, full legal textCreative Commons · CC BY 4.0 · checked on August 6, 2026creativecommons.org/licenses/by/4.0/legalcode.en
  2. SIL Open Font License 1.1, the licence of the embedded typefacesSIL International · OFL 1.1 · checked on August 6, 2026openfontlicense.org
  3. Web Content Accessibility Guidelines 2.2, the standard this site aims atWorld Wide Web Consortium · W3C recommendation · checked on August 6, 2026www.w3.org/TR/WCAG22
  4. The security contact file standard, served by this site at the reserved addressIETF, RFC 9116 · public standard · checked on August 6, 2026www.rfc-editor.org/rfc/rfc9116.html

What could not be verified, and is therefore not written

No search volume appears anywhere on this site, in any language. The tools that publish such figures require an advertising account or give only relative indices: an invented volume figure inside a grant application is a lie, and leaving the figure out is the only honest remedy.

The exact number of titles in each catalogue cited above is not written either. Those numbers move, and a number recorded once and then copied becomes wrong without anyone noticing. What is written is the licences and the scope, which rarely change, and the address at which anyone can go and count.

The teaching quality of these works is not judged here. The house verified that they exist, what they cover and under which licence. Calling a textbook good requires having used it in a classroom, and that cannot be done from a browser.

An address on this page that no longer answers, or a licence that has changed, deserves a report. The external links on this site are never called automatically at release time: a release does not depend on dozens of third-party sites being up at the same instant.

What these sources document