When people ask for source, it's usually in response to a fringe claim that is not well documented. This is not that. It has been well documented and discussed in the last 5 to 10 years and there are plenty of sources available with a little bit of searching. I have a hard time believing you are asking in good faith.
Most likely they are asking in good faith, they just aren't familiar with it because they live on another continent, and they're asking because people here might know a particularly good source that's better than whatever they get in an online search.
But yeah, in this case, an online search would likely come up with plenty of good enough accounts.