# Third-party notices

## WeBWorK Open Problem Library

The interactive edition contains adapted problem files obtained from the
WeBWorK Open Problem Library at commit
`521448225da9a2dc4ebf1ed6258f7afe2f1b5eac`. The OPL notice states that,
unless otherwise indicated, copyrights are held by the contributing authors
and contributions are licensed under CC BY-NC-SA 3.0 Unported; contributors
may instead specify another OSI-approved license.

Original problem sources and their contributor notices are in `opl-sources/`;
the verbatim licence is in `notices/OPL_LICENSE`.
The Indonesian adaptations retain the applicable component attribution,
NonCommercial, and ShareAlike conditions.

## PreTeXt and Runestone output

The HTML reader includes generated runtime assets from PreTeXt and Runestone.
Those software assets retain their upstream notices and licenses. Their
presence does not change the CC license governing the book content.

## Images and authored assets

Images and diagrams inherited from Oscar Levin's fourth-edition repository are
treated as components of that book under its active CC BY-NC-SA 4.0 notice,
unless a file carries a more specific notice. Source identities and exact
hashes are retained in the editable-source and provenance packages.