As a general rule, isolated images or parts of other works cannot be included in a work or exercise unless:
- These are self-produced contents (for which the exploitation rights have not been transferred to third parties).
- Permission is obtained from the owner of the exploitation rights (the author or others to whom they may have been transferred).
- It is a work with a free access license (Creative Commons or similar).
- This is a work of public domain (the author died more than 80 years ago, or 70 if he passed away after December 7, 1987).
However, in application of the32 article of the Intellectual Property Law (LPI), isolated images or fragments of other works can be incorporated even if none of the previous cases apply, as long as the following conditions are met:
- That it is a work that has already been published
- That its inclusion is made as a quote or for its analysis, commentary or critical judgment. For example, an image that guarantees the understanding of the text can be included, but not an image with purely decorative purposes.
- To be used only for teaching or research purposes.
- That the work be used to the extent justified by the purpose of this incorporation. For example, reproducing only the fragment strictly necessary to make the commentary, not other more extensive parts of the work.
- Mention must be made of the source and author of the work used.
It is important to keep in mind that:
- It is recommended to rely on article 32 of the LPI only if it is very clear that all its requirements can be met.
- If the work you want to use was acquired through a contract or license of use, it is also necessary to check whether the supplier's clauses allow the desired use.
When incorporating an image, the source must be indicated below the image, in smaller font (for example, size 10), or if it is self-produced (Source: self-produced). However, the image must be centered on the page and, if applicable, must maintain a legible size that is proportional to the text. Example:

Also, figures must be referenced in the text (for example: “as shown in Figure 3”, “as shown in Figure 4.3.”) and must be included in a separate list indicating the page where they appear. Example:
