Bring it anyway. You'll be kicking yourself when that 30 sec. "gimme" question would have been a quick table look up, and you never know when you might have discipline crossover. Plus, it's not like it's going to take up that much room in your bag/cart/what have you. I'd be hesitant about bringing in a full encyclopedia set or lots of undergrad books, but we all rolled into exam sites with way more than we needed. Call it a security blanket.