Here are some helpful sources for finding a wide variety of images for presentations and papers.
Remember to check your rights permissions at all times. Images must be properly cited, like any other source. Learn more about the best practices for copying and using images.
Tineye.com can help you trace the origins of some images.
gfpeck. (2010, March 29). Create [image]. Retrieved from https://www.flickr.com/photos/wespeck/4473683746/