If you use a source of information in your presentation, you should acknowledge that source in the usual way, i.e. citation and referencing. This especially applies to images.
If you use a powerpoint presentation or similar visual tool, you should provide a bibliography at the end of the presentation, with appropriate in-text citation where you use sources of information. This also applies to use of images.
"If students incorporate the thoughts and ideas of others into the presentation, this must be acknowledged" (International Baccalaureate, 2013, p. 56).
Reference
International Baccalaureate. (2013). Theory of Knowledge Guide, first assessment 2015. Cardiff, UK: International Baccalaureate Organization.
*The above text is from Dr. Anthony Tilke's excellent libguide on TOK. Check it out for many useful resources!
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