I used a jeppesen computer disc for my ATPL.the smallest u can get.(cr5)
http://www.marvgolden.com/flight-com...jeppesencr.htm
I was always in the middle of 2 answers, so I had just to pick one answer.
passed navigation exam with 78%, and a 20$ computer disc...just lucky!
I dont suggest them if you do your ATPL.