Whenever you use information from a source, you must always acknowledge where it comes from – and make it clear when you are using it and how often it needs to be cited.

Introducing a source

Always cite a new source in the first sentence where you use it. There are two ways to do this:

Narrative citation puts the focus on the author – use this when who said it is important:
According to Goksøyr (2023), sports history shows that ... (p. 59).

Parenthetical citation puts the focus on the idea or finding – use this when what was said is more important than who said it:
The post-war years were ... (Goksøyr, 2023, pp. 93-97).

When you use the same source in a new paragraph

Even if it is the same source, you must cite it again at the start of each new paragraph.

When you use the same source throughout a long paragraph

When paraphrasing from a single source throughout a longer paragraph, introduce the source in the first sentence:

Goksøyr (2022) points out that … (p. 90).

Later in the paragraph you can write: Goksøyr further argues that … You do not need to repeat the year, unless you introduce a new source or enough text has passed that it may be unclear which source you are referring to.

When you use multiple sources in the same paragraph

If you draw on several different sources in the same paragraph, introduce each new source as soon as you refer to it.

Example:

Academic writing is a skill that develops over time, and it is important to learn the fundamentals early. According to Hansen (2021, p. 19), … Anderssen et al. (2022) further note that source citation is a key aspect of academic writing, particularly for avoiding plagiarism (p. 45). Smith and Brown (2020) have also shown that students who receive early training in citation perform better in exams (pp. 3, 5). This underscores the importance of building strong academic skills from the start of one's studies.

(The text and sources are fictional and used for illustrative purposes only.)

In brief

Cite the source in the first sentence where you use it.
Repeat the citation at the start of each new paragraph if you are still using the same source.
In long paragraphs: repeat the citation if it becomes unclear who you are referring to.
When using multiple sources in the same paragraph: make it clear who says what.