Citing sources at university follows one basic rule: everything that does not come from you must be marked, directly at the point where you use it. Word-for-word takeovers go in quotation marks, paraphrases get a source reference, and at the end all sources are listed in a bibliography. Which style applies is usually set by your department.
Here you will find the most important rules for citing at university, the difference between direct and indirect quotes, the common citation styles with examples, and the mistakes that occur most often in papers.
The most important points at a glance
- Direct quotes are word for word and appear in quotation marks. Indirect quotes restate the meaning in your own words and still need a source.
- There is no single citation style. What counts are the requirements of your department or supervisor.
- Use one style throughout the whole paper. Mixed forms are noticed and cost marks.
- Every source in the text appears in the bibliography, and every source in the bibliography appears in the text.
- Anyone who takes foreign ideas without a reference risks an accusation of plagiarism, even by carelessness.
Why is citing sources at university so important?
Citing makes your work verifiable. Readers should be able to trace where a statement comes from and check it against the original. At the same time, you show that you know the state of research and build your arguments on it.
There is also protection against accusations. Missing references can be treated as deception, even if there was no intent. The consequences are set out in your examination regulations. More on this subject is in our article on plagiarism during your studies (in German).
What is the difference between a direct and an indirect quote?
A direct quote takes the wording of a source unchanged, an indirect quote restates the content in your own words. Both need a reference. In most papers indirect quotes predominate, because they fit better into your own text.
| Feature | Direct quote | Indirect quote |
|---|---|---|
| Wording | Unchanged from the source | Your own wording |
| Quotation marks | Yes | No |
| Source reference | Always, with page number | Always, page number depending on the requirements |
| When useful | Definitions, concise wording, analysis of the wording | Summaries, integration into your own argument |
How do I quote directly?
Put the taken text in quotation marks and give the source directly afterwards. Do not change the wording, not even errors in the original. Mark omissions with square brackets and ellipses, and mark your own additions in square brackets as well.
Example (invented for illustration): Müller defines research as “a continuous process of approximation” (Müller 2020, p. 45). Example with an omission: “Research is […] a continuous process.”
Longer direct quotes are set as an indented block at many universities, often from about three lines. The exact limit and the formatting follow the requirements of your department.
How do I quote indirectly?
Restate the idea in your own words and with your own sentence structure, without quotation marks, and cite it. It is not enough to swap a few words. That would be a mere reshaping of the original and can also count as plagiarism.
Common is a reference such as “cf. Müller 2020, p. 45f.” or an introduction in the text, such as “Müller (2020) points out that …”. Whether you must give page numbers for indirect quotes is set by your university’s guidelines. When in doubt, include them.
Which citation styles exist?
The common styles differ mainly in where the reference appears and how the bibliography is structured. Departments and journals have their own preferences, so what your department requires always counts.
| Style | Reference in the text | Typical subjects |
|---|---|---|
| APA | Author and year in brackets, for example (Schmidt, 2023) | Psychology, social sciences |
| Harvard | Author and year, often without a comma, for example (Schmidt 2023) | Business and social sciences |
| Chicago | Footnotes or the author-date variant | Humanities |
| MLA | Author and page, for example (Schmidt 23) | Language and literature studies |
| German citation style with footnotes | Full reference in the footnote | Law and humanities |
The assignment of subjects is a rule of thumb. What counts is the requirement of your supervisor or institute. Ask there before you start.
How does the APA style work?
In APA the surname and the year of publication appear in brackets in the text, and for direct quotes the page as well. The bibliography is sorted alphabetically by surname.
Example (invented for illustration): Schmidt, M. (2023). Die Kunst des Zitierens. Wissenschaftsverlag.
How does the Harvard style work?
The Harvard style also uses author and year in the text. It is less strictly standardised than APA, so details differ between universities and institutes. Check the template you have been given and apply it consistently.
How do I cite with footnotes?
With footnotes, a superscript number appears in the text and the reference is at the bottom of the page. The first time, the source is usually given in full, later often in short form. The bibliography at the end remains compulsory. Here too, the format and short references are set by your department.
What does a bibliography look like?
The bibliography lists all sources you have used in the text, following one consistent scheme and usually in alphabetical order. Required details depend on the type of source: author, year, title and location. For books, add the publisher and, if applicable, the edition. For journal articles, add the journal, volume, issue and pages. For websites, add the address and the access date.
| Type of source | Components (example, invented) |
|---|---|
| Book | Schmidt, M. (2023). Die Kunst des Zitierens. Berlin: Wissenschaftsverlag. |
| Chapter in an edited volume | Mayer, S. (2020). Regeln für präzises Zitieren. In: Huber, A. (ed.), Leitfaden für wissenschaftliches Arbeiten (pp. 112-130). München: Lehrbuchverlag. |
| Journal article | Klein, T. (2021). Plagiatsvermeidung in der Praxis. Journal für Hochschuldidaktik, 15(2), 78-92. |
| Website | Author or institution (year). Title. Address, access date |
The examples show the principle. Punctuation and the order of details differ between styles. Use a template from your department as the benchmark.
A reference manager such as Zotero, Mendeley or Citavi takes much of the work off your hands. You enter the data once, and the program formats references and bibliography in the chosen style. Still check the output, because faulty imports do happen.
How do I cite sources I know only second-hand?
A secondary citation applies when you take over a statement that you found only in another author’s work. In principle, you should obtain the original source and read it yourself. Only if it is not accessible, for example because it is out of print, may you cite via the secondary source, and you must make that clear.
The usual addition is “cited in”, for example: Müller 1980, cited in Schmidt 2020, p. 75. In the bibliography only the work you actually read then appears.
How do I cite AI and AI sources?
An AI tool is not a source in the scholarly sense, because its statements cannot be traced back to a verifiable author. Support facts with the primary source that you have read yourself. Whether and how you must disclose the use of a tool is governed by your university and examiners. The rules are in our article on AI in your studies (in German). Some citation style guides contain notes on how to disclose AI use. Check the current version of your style and ask if in doubt.
Which mistakes happen most often when citing?
- Missing reference: a borrowed idea appears in the text without a source.
- Faulty rewording: only individual words are swapped.
- Mixed styles: author-year in the text, another scheme in the bibliography.
- Incomplete bibliographies: sources are missing, or they are listed without appearing in the text.
- Missing page numbers for direct quotes.
- Secondary literature only: the original was never read.
- Unchecked online sources without an author and date.
How to find and assess good sources is explained in our article on academic research and evaluating sources (in German).
How do I proceed step by step when citing?
- Find out at the start which citation style is required.
- Record every source immediately with all details, ideally in a reference manager.
- Note page numbers while reading and mark whether you take something word for word or in substance.
- Add references while you write, not only at the end.
- Finally, check text and bibliography entry by entry.
If you are working on your final thesis right now, a guide to writing a bachelor’s thesis (in German) with timeline and structure helps. Under pressure and time constraints, it is worth looking at mental health during your studies (in German).
Frequently asked questions
How do I cite indirectly and correctly?
Formulate the idea in your own words and sentence structure, use no quotation marks, and cite the source, for example with “cf.” and a page reference. Swapping a few words is not enough. Whether page numbers are required is stated in your university’s guidelines.
Which citation style is the right one?
The one your department or supervisor requires. No style applies everywhere. The choice depends on the subject: APA is common in psychology and the social sciences, footnotes in the humanities and law. Ask for a template.
Do I need a bibliography if I use footnotes?
As a rule, yes. The footnote gives the reference at the point of use, and the bibliography lists all sources together. Whether an exception applies is stated in the guidelines of your institute.
How do I cite internet sources?
Give the author or institution, year, title, the exact address and the access date, as far as the style requires. First check whether the source is reliable and whether a citable version exists, such as a specialist publication instead of a blog post.
How to proceed now
- Ask which citation style is required and download the template of your department.
- Set up a reference manager and record your sources from the start.
- Mark every borrowed passage while you write and distinguish word for word from paraphrase.
- Plan time before submission to compare text and bibliography.
Related articles
- Avoiding plagiarism: what to watch for when writing (in German)
- Academic research: finding and evaluating sources (in German)
- Writing a bachelor’s thesis: guide, timeline and tips (in German)
- AI in your studies: what is allowed and how to use tools properly (in German)
Last updated: October 2026. This guide is general information, not individual advice. The German version is authoritative.
