When citing online sources, you should follow these two rules:
- Understand the principle: Readers must be able to classify the source and find it themselves based on your reference.
- Cite consistently: Stick to the chosen citation style throughout your work.
We recommend treating a website like a printed publication – that means providing the author(s), date, and title whenever possible, and using the web address instead of publisher and location.

In the reference list, you list a website as follows:
Last name, First name (DD.MM.YYYY): Title. If applicable, publishing institution. URL (retrieved on DD.MM.YY).
Examples:
In the reference list:
Böhme, Stefan/Unte, Pia/Werner, Daniel (2009): Women in STEM professions in Bavaria. Ed. by Institute for Employment Research (Reports and analyses from the regional research network). http://doku.iab.de/regional/BY/2009/regional_by_0109.pdf (retrieved on 14.10.2024).
Short citation in the text or in a footnote:
Böhme et al. 2009, p. 12
Older recommendations for citing online sources sometimes suggest listing them separately.

Similarly, the note “Online on the internet” can be omitted – readers will recognize this from the web address.
Websites have some specific characteristics compared to printed publications that can cause difficulties:
- The information is often incomplete, e.g., publication date, author(s), or page numbers may be missing.
- Websites are unstable, i.e., they can easily be deleted, changed, or moved.
Of course, you can only include what is given. However, if the information is incomplete, you should check whether this source really meets scientific standards. You might find a better source.
If you decide to cite the source anyway, use the available information to ensure traceability:
If the date is missing, use “n.d.” for “no date”.
Examples:
In the reference list:
wildwasser (n.d.): Info and help: What is sexual abuse? https://www.wildwasser.de/fragen-und-antworten/was-ist-sexueller-missbrauch (retrieved on 14.10.2021).
Short citation in the text or in a footnote:
wildwasser n.d.
If the online source is an unusual format – a blog post, a tweet, a YouTube video etc. – include the format in square brackets after the title.
Examples:
In the reference list:
Freakonomics (29.10.2010): E-ZPass is a life-saver (literally) [Blog post]. http://www.freakonomics.com/2010/10/29/e-zpass-is-a-life-saver-literally (retrieved on 14.10.2021).
Short citation in the text or in a footnote:
Freakonomics 29.10.2010
Here today, gone tomorrow – online sources can easily be moved or deleted. This characteristic of online sources conflicts with the requirement for scientific sources: ensuring traceability.
This does not mean that you must never cite from the internet, but you should consider the following tips:
- Check whether you can find an equivalent printed source.
- Choose online sources from reputable publishers, such as e.g., universities, academic journals, or ministries. This does not guarantee the source will still be online tomorrow, but it increases the probability.

Examples:
In the reference list:
Media Education Research Association Southwest [MFPS] (Ed.) (2011): JIM Study 2011. Youth, Information, (Multi-) Media. Basic study on media usage of 12- to 19-year-olds. Stuttgart. https://www.mpfs.de/fileadmin/files/Studien/JIM/2011/JIM_Studie_2011.pdf (last updated on 10.11.2011, retrieved on 14.10.2021).
Short citation in the text or in a footnote:
MFPS 2011

Usually, however, this is not necessary.
Literature: APA Style (2010): How do you cite website material that has no author, no year, and no page numbers? http://www.apastyle.org/learn/faqs/cite-website-material.aspx (retrieved on 14.10.2021).
Literature: Bleuel, Jens (2001): Citing online sources. In: Hug, Theo (Ed.): How does science acquire knowledge? Volume 1: Introduction to academic work. Hohengehren: Schneider. http://www.bleuel.com/ip-zit.pdf (retrieved on 14.10.2021).
How do I cite online books?
The scheme is the same as for journals and other online sources:
Last name, First name (Year): Title. Place of publication: Publisher. URL (retrieved on DD.MM.YY).
When are online sources citable?
Be aware of the weaknesses of online sources and consider for what purpose you want to cite them. If it is still the best source, you can certainly cite online sources. The name of an author (or several) or an organization and a date should be available as minimum information.
This article was published in August 2025 and last updated in November 2024.







