Can I cite lecture slides in a bachelor's thesis at all?

Formally yes, academically only with caveats. Slides are grey literature — not peer-reviewed, usually only available internally. For a substantive claim you need the original source the slide refers to. Slides only work as a citation when you're referring to the lecturer's own unpublished view.

How do I cite slides that have no date?

In APA 7 write 'n.d.' (no date) instead of the year. If the slide shows the term, use it: (Mueller, Fall 2024). If there's no dating and you got the slides second-hand, drop them entirely and cite whatever publication the slide itself refers to.

What's the difference between a lecture and a course script?

A script (Skript, in German-speaking universities) is a multi-page text document issued by the department; slides are the presentation pages. Both are unpublished in the strict sense, but a printed script with an ISBN or in a university series counts as a publication and is cited like a book.

Citing lecture slides and handouts — what's allowed, what isn't

Every bachelor’s or master’s thesis hits the same question sooner or later: the lecturer gave a definition in class that fits perfectly into your chapter — and you can’t find it anywhere else. Can you cite the slide? Is the script in the OLAT or Moodle course a real academic source? And if so, what goes into the reference list? This post covers when lecture slides and course materials actually count, how to cite them cleanly in APA, Harvard, and Chicago, and what tells an examiner instantly that you’re papering over weak source choice with correct formatting.

First question: is this an academic source at all?

Lecture slides and course scripts are grey literature — material produced outside the traditional publishing pipeline, without peer review, usually accessible only to a limited audience. That’s not automatic disqualification, but it sets a high bar for use in a thesis.

There are three cases where slides genuinely work as a source:

The slide itself is your object of study. You’re analysing higher-education teaching, comparing pedagogical concepts, or investigating how a topic gets taught. Then the slides are your material.
The lecturer expresses their own, unpublished position. A model, classification, or interpretation they developed, not yet in a book or article.
No other medium exists. Historical example: an interim result from an ongoing research project that the lecturer presented only in class.

What does not fly: citing a slide because it neatly restates what’s in the book that the lecturer credits at the bottom of the slide. In that case, cite the book, not the slide. Anything else is a secondary citation for convenience — and secondary citations are the weakest evidence any thesis can carry.

The rule: always chase the original

Almost every academic slide has a source at the bottom or in a footnote: “after Bandura, 1997” or “Source: Mueller (2019, p. 42)”. That line is your task. Head to the library or Google Scholar, open Bandura 1997 yourself, and cite the original. The slide was the delivery; the source is the evidence.

This rule sounds trivial but gets broken in maybe half of all student theses. Examiners see it immediately: a reference list where lecture slides appear instead of the obvious primary literature is a red flag for shallow research.

APA 7 — slides and handouts

APA 7 treats slides as presentation material with a format tag in square brackets.

In-text:

Self-efficacy is the expectation of being able to master a task successfully (Mueller, 2024, slide 12).

Instead of a page number you give the slide number. For a running-text script, use the regular page number.

Reference list (slides on a closed learning platform like OLAT / Moodle):

Mueller, H. (2024). Motivational psychology: Self-efficacy and goal orientation [PowerPoint slides]. University of Zurich, OLAT. https://olat.uzh.ch/…

Reference list (publicly available script / PDF):

Weber, K. (2023). Introduction to qualitative social research [Lecture script]. University of Bern. https://www.unibe.ch/…/qualitative-research-script.pdf

If the slides are only accessible internally (password-protected, OLAT, Moodle), APA 7 adds an important note: since external readers can’t retrieve the source, it actually belongs in the text as personal communication — without an entry in the reference list:

Mueller (personal communication, April 12, 2024) defined self-efficacy as …

In practice most departments accept the first variant (with reference-list entry) anyway, because your examiner can reach the slides via the university login. When in doubt, ask the secretariat.

Harvard — lighter, but equally strict

Harvard style has no single fixed template like APA, but follows the same principle: author, year, title, format tag, place.

In-text:

(Mueller 2024, slide 12)

Reference list:

Mueller, H. (2024) Motivational psychology: Self-efficacy and goal orientation [Lecture slides]. University of Zurich, Fall term 2024.

For a printed or PDF-distributed script:

Weber, K. (2023) Introduction to qualitative social research. Lecture script. Bern: University of Bern.

Harvard doesn’t demand the square-bracket tag APA uses, but marking the material as “Lecture script” or “Handout” is mandatory — otherwise readers would take the source for a book.

Chicago — footnote and bibliography

Chicago Notes puts unpublished materials in a dedicated category. The footnote contains author, title, format tag, institution, date.

Footnote (first mention):

¹ Hans Mueller, “Motivational Psychology: Self-Efficacy and Goal Orientation” (lecture slides, University of Zurich, Fall term 2024), slide 12.

Footnote (short form):

² Mueller, “Motivational Psychology,” slide 15.

Bibliography:

Mueller, Hans. “Motivational Psychology: Self-Efficacy and Goal Orientation.” Lecture slides, University of Zurich, Fall term 2024.

Chicago makes no structural distinction between slides and script — both fall under “unpublished lecture materials” and belong in the bibliography with that label.

The special case: recorded lectures

More and more lectures are recorded and live on OLAT, Moodle, Panopto, or YouTube. These are formally videos, not slides — and they’re cited differently.

APA 7:

Mueller, H. (2024, April 12). Motivational psychology: Self-efficacy [Video]. University of Zurich, OLAT. https://olat.uzh.ch/…

For a direct quotation you give a timestamp instead of a slide number: (Mueller, 2024, 12:34). Timestamps do for videos what page numbers do for books — without them nobody can verify the claim. More on citing audiovisual sources in the post on podcasts, videos, and social media.

What you should never do

Insert screenshots of slides without citation. If you copy a figure from a lecture, you need (a) the source line under the figure, (b) an entry in the list of figures, (c) — if the lecturer didn’t create the figure themselves — the original source the figure came from. Never take a figure “after Mueller (2024, slide 8)” and omit the original Bandura (1997) that appears in small print on the slide.

Cite slides even though you have the book. If Bandura 1997 is on your shelf and you cite Mueller’s slide anyway because it’s faster — every examiner spots this the moment they cross-check the reference list against the text.

Hide secondary citations. If Mueller’s slide reads “after Bandura (1997)” and you quote from it, that’s a secondary citation: “Bandura (1997, cited in Mueller, 2024, slide 12)”. The original (Bandura) does not go in the reference list — only the slide does. But honestly: if Bandura 1997 is retrievable, get it. Secondary citations are a fallback, not a default — more in the article on secondary citations.

Assign undated slides a made-up year. If there’s no date on the slide and you don’t know which term it’s from, write “n.d.” — not the year you downloaded it.

Checklist before submission

For every slide, checked whether the original source is citable — and if so, cited the original instead of the slide.
Format tag ([PowerPoint slides], [Lecture script]) present in the reference list.
Institution and term/year given.
For internal slides (OLAT/Moodle), clarified with the department whether a reference-list entry is accepted — or whether they belong in-text as personal communication only.
For screenshots from slides, the original source from the slide appears in the citation, not the slide itself.
No secondary citation where the primary work could be obtained in half an hour.

The real test: does the slide actually say what you claim?

Formally correct citations to lecture slides don’t protect against the substantive error. If you write “Mueller (2024, slide 12) defines self-efficacy as …” but slide 12 actually explains goal orientation — that’s a mistake no format check will catch.

That’s exactly where Acurio comes in: you upload your thesis, plus the cited materials — slide PDFs and scripts included — and Acurio checks for every citation whether the claim in your text is really supported by the source. For slides this is especially valuable, because you often paraphrase from memory what was said in the lecture, and it’s easy to drift from what the slide actually said.

Lecture slides and course scripts are permissible but weak sources. Use them when nothing better exists, label them correctly, and replace them with primary literature as soon as you have it in hand. A bachelor’s thesis built 80% on slides reads like one built 80% on Wikipedia — even if the formatting is impeccable.