Can Ultradox skip printing a document if a given e-mail address has been entered previously?

[guard...@gmail.com]

I have Ultradox set up to print a document after a customer fills out a Google form. I want to avoid printing duplicate documents for the same customer. Is there a way to get Ultradox to check previously entered data, such as an e-mail address and get it to skip printing the the document if the current entry matches previously entered data?