"Dat" not only means "that", but also an admiration (perhaps of the lusty variety) for the item thereafter described. Most infamously, the meme "Dat Ass" is us

"Dat" not only means "that", but also an admiration (perhaps of the lusty variety) for the item thereafter described. Most infamously, the meme "Dat Ass" is used, but "Dat X" is commonly used on Reddit, Imgur, and other meme sites to express attraction to some object. In this case, "Dat Reference List" just means that the reference list is very impressive.