Dude needed to get his wildlife handler paperwork or shut the fuck up. He claimed he was getting it repeatedly and there’s evidence he did fuck all.
He got his animals killed by failing to adhere to the basic laws he already knew about. It wasn’t a surprise.
What you’re describing is called a citation or reference tree and they are used to visualize complex set of references. Web of Science has a nice one, Scopus also has a tree view, I believe. Google Scholar has the information to make one, but doesn’t.