This is a medical article on the strength of memory after traumatic events. It is an interesting take on whether we can trust ourselves to be able to remember events properly.
In a new 2017 article, the New York Times goes over the events with various still living members of JFK's security detail. They remember the events and discuss how quickly it all happened.
This is a collection of all of the testimonies and personal writings of David Powers. It was published by the JFK Library and contains every statement he made about the assassination.