These documents identify the dates vehicles were allocated for delivery and the number to be delivered. They also show the date they shipped and in some cases will show the date of arrival and the train number. Though mostly accurate these should not be considered the absolute truth. Especially in the case where other, more compelling, evidence might contradict.
The documents do vary in quality and there are some that you have to work at to make out. Below are the sets that are currently available. Just click on the cart to add them to you shopping cart.