Cite the original presentation as:

Morrison, H., & Salhab, J. (2015, September). Sustaining the knowledge commons: Open access scholarship, IDRC. Overview of the Sustaining the Knowledge Commons project presented at the International Development Reesarch Center (IDRC), Ottawa. Retrieved from http://ruor.uottawa.ca/handle/10393/32845

The presentation powerpoint can also be downloaded from this link.