PEXELS Videos provides a repository of short video clips from various sources that are eligible for re-use and modification.
Sample Notice of Use
Turning Pages video made available under Creative Commons 1.0 Universal releasing the work to the public domain. The work can be copied, modified, distributed and performed without providing attribution.
Sample MLA Citation
"Turning Pages" PEXELS Videos, videos.pexels.com/videos/turning-pages-856242. Accessed 26 Jan. 2019.