Lecture Notes or Slides
Author, A. A. (year). Title of presentation [Lecture notes or PowerPoint slides]. Retrieved from http://xxxxx
Notes
In this specific example, no author is clear, so the title slides into the author position.
If notes or slides are only available from the presenter, someone who took notes during a lecture, or in a content management system (such as Blackboard, Canvas, or Moodle), cite as personal communication. Personal communication is not retrievable by other researchers and is cited in text only.
More Examples
Author, A. A. (year). Title of presentation [Lecture notes or PowerPoint slides]. Retrieved from http://xxxxx
No Child Left Behind: A new era in education [PowerPoint slides]. (n.d.). Retrieved from the U.S. Department of Education website: http://www2.ed.gov/nclb/overview/intro/presentation/presentation.ppt