I gave you the Clinton Foundation page declaring it. Use Crunchbase.com , plug in the doner , start digging, look at dates on Crunchbase. Its how we research.  If you want a receipt, I could probably get you one. You have to know where to look. Donations such as these are documented in many places. Also the donor should be in the public as well. You have a spider stuck in the web. Its often amazing the places these critters take you. The more you do it , like anything else , the better you get. In this particular case, its bad, many books have already been written and documents grabbed. So sometimes you get the blowback, where they try to delete or scrub stuff. This is a page capture for example.