Self-plagiarism - as it is obvious from the term - is also plagiarism. In practical terms it means that one must not submit the same paper or very similar version of it for several courses, just like it is not acceptable to submit the same paper or very similar version of it for publication to different journals. If the topics of two of your courses are highly relevant for your dissertation and could be linked for an interesting insight, you may discuss it with the tutors of both courses that writing a paper - double the length of a single assignment - would help you create a paper that you could use for your dissertation. If the idea makes good sense, the request will be accepted.

As outlined above, self-plagiarism is not acceptable. However, the research papers that PhD researchers publish are then often incorporated in their dissertation. This is fine, but a footnote must be inserted in the dissertation to indicate if a particular section or chapter is a modified version of an article published earlier along with the publication data. A similar indication has to be provided if an article is republished in another language.

And finally a word about copyright issues: While textual quotations - with the appropriate documentation - are integral parts of academic texts, reproducing visual materials (tables, figures, photos, etc.) is not always straightforward. The permission of the publisher of the publication where the visual in question originally appeared must be obtained for using a visual in a published material. Many publishers operate an online platform for this purpose and permission is often granted for free fro academic purposes. If the permission cannot be obtained, the appearance of the original visual can be redrafted or modified, but care must be taken not to modify the content. The caption then has to show that this is a visual based on the original author's work and the reference must also be provided.

As dissertations are not subject to copyright but are considered official documents, permission is not necessary to reproduce a visual. However, if it is published later, permission must be obtained.

The Code of Research Ethics that applies to all researchers including PhD students is available here.