I'll defer to David in terms of some of the source reporting from a CSIS perspective, but I can only repeat what you just said. When we went out to those 17 agencies and departments representing the breadth and scope of the security intelligence community, we looked at all sources.
Everything that came up to us was intelligence, open sources, consultations with academics right across the board. What you see reflected in the report is a composite picture of all the evidence, all the intelligence, and all the analysis, open-sourced right on down across the spectrum.