Get Comey and get his memo and put him under oath. Also remind him that with this revelation he basiadmits he lied possibly under oath and why it is he is coming out with this now. Also, subpoena acting director McCabe testified to the opposite of what Comey is saying now.
Comey WAS UNDER OATH when he testified to the Senate Committee yesterday. Comey seems like he was going to give Trump the benefit of the doubt in this request, but the admission by Donald Trump that he fired Comey because of the "Russia thing" is an admission of obstruction of justice, and Comey's memo confirms this.
Comey is known for keeping meticulous notes on meetings, and given his background as a highly successful prosecutor, this makes sense.
Comey also has more integrity and creditability than Trump. If push comes to shove, and it will, Comey is believable and Trump is not.