CiteWise

When to cite sources: the decision tree

Pick the sentence you’re unsure about and answer a few questions. You’ll get a verdict, the reason, and an example of where the citation goes.

Question 1

Did this sentence come from, or depend on, something you read, watched or heard?

Include books, articles, websites, lectures, videos, AI tools your course allows, interviews and datasets.

Why the decision matters more than the format

Formatting mistakes cost a mark or two. Missing citations can trigger an academic integrity case, even when the student honestly forgot. Most universities define plagiarism as presenting someone else’s words or ideas as your own, which is why paraphrasing without a citation counts.

The flip side: citing every sentence buries your own thinking. Markers want to see where the sources stop and your analysis starts. That’s why the tree asks whether a sentence is your interpretation of evidence: that sentence stays uncited, and it’s often the one that earns the marks.

Ready to test it? Try the practice exercises, or paste your paragraph into the placement checker.

Questions students ask

When do you need to cite a source?
Whenever you use someone else’s exact words, paraphrase their ideas, use their data, statistics, images or figures, or rely on a specific argument they made. You don’t cite your own ideas or genuine common knowledge.
What counts as common knowledge?
Facts a general reader already knows and could find undocumented in several general sources, such as the year World War II ended. Specific statistics, recent research and disputed claims are not common knowledge.
Do I need to cite something I already knew?
If you learned it from a particular source for this assignment, or your reader wouldn’t know it, cite it. Your prior knowledge only counts as common knowledge if it is widely known by your audience.
Do I cite AI tools like chatbots?
Follow your course policy first. APA and MLA both publish guidance for citing generative AI output; in general, if you quote or paraphrase AI-generated text, you describe how you used the tool and cite it.