Citations and traceability in summaries
Updated on August 5, 2026
Citations are the feature that makes an AI-generated summary trustworthy. Without them, you have no way to know whether a claim comes from the book or was made up. With them, you can check in seconds.
How citations look
Inside the text of each summary section you will find numbers in brackets, such as [1] or [2]. Each number corresponds to a specific fragment from one of the books included in the summary. If the fragment draws from several books, you may see multiple numbers in a row.
Hovering over a number shows a pop-up card with:
- A thumbnail of the book page where the fragment appears.
- The book title.
- The page number.
- The quoted text (when available).
What happens when you click a citation
Clicking the number opens the reader directly on the page that contains the fragment. If the quoted text is available, the reader highlights the corresponding paragraph so you can find it straight away.
If you need to open the citation in a new tab instead of the current view, right-click the number: a menu appears with Open and Open in new tab options.
Why citations are the key to trusting an AI summary
AI models can make mistakes: they may rephrase an idea imprecisely, mix information from different contexts, or, less often, generate a claim that is not in the book. The citation lets you verify directly whether what the summary says matches what the book says.
Before using an important claim in a paper, presentation, or decision, verify the corresponding citation in the book.
References section
When downloading the summary, if you enable the Include references option, the exported file includes a References section at the end listing the books cited in the summary.
Frequently asked questions
What happens if I click a citation and the book is no longer in my library? Theca shows a notice that the referenced resource is not available. This happens if you deleted the book after generating the summary.
Are citations 100% accurate? AI can make mistakes. The citation points to the fragment the model used as its source, but you should always verify important claims directly in the original text.
Why do some sections have no citations? A section may end up without citations if the search found no relevant fragments in the selected books. In that case the node may appear with a No matches or Insufficient sources status.
Can I see all references in a summary at once? The references section appears in the exported file when you enable Include references. In the detail view, citations are distributed within the text of each section.
Next step
- Summaries — return to the full summary creation flow.
- Cross-book summaries — combine several sources and see citations from each one.
- Search — search passages directly in your library without generating a summary.