In my research internship report, I'm mentioning a successful deep learning experiment. I performed it because another researcher told me it gave them good results for a similar problem.
I need to justify why I tried this, but I can't cite something un-published like this conversation. Is it appropriate to mention it in a footnote, like "according to other researchers, [...]"? Should I search for a citable source that says the same thing, or just drop the justification?