Licence
What you may do with CTRI books.
The text, figures and worked examples in CTRI books are licensed under Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0).
You may
- read, download and print the books for free;
- share them, and adapt them for teaching, with credit to CTRI and a link to the licence;
- cite a version. Every released PDF is kept on the Previous versions page, so a teacher who cites version 1.2 can open exactly that text.
You may not
- sell the books or use them commercially.
Exam questions
Past exam questions belong to the exam bodies, such as the West African Examinations Council. CTRI organises and explains them for study and does not own them. Our solutions are our own working, not an official marking scheme.