Answered By: Amy Gilbert Last Updated: Jul 17, 2014 Views: 22357
You would cite this as is it is part of a lecture, with just the title of the powerpoint or slide and (n.d.) for no date (example below). Sources that have no date or author do not carry as much scholarly weight as a published article, however. Use sparingly.
Source: Purdue's Online Writing Lab (OWL)
Federal regulations of chemicals in the environment [PowerPoint slides] (n.d.). Retrieved from http://siri.uvm.edu/ppt/40hrenv/index.html
Roberts, K. F. (1998). Federal regulations of chemicals in the environment [PowerPoint slides]. Retrieved from http://siri.uvm.edu/ppt/40hrenv/index.html