Additional Resources needed for Combat Trained Giant Gecko?

[FLite]

Currently I have the Core, the APG, and ultimate equipment. Do I need bestiary 3 to have a riding gecko from ultimate equipment? If I want the smaller combat trained gecko from Adventurer Archive do I need that book as well? or is it listed elsewhere (it looks like most of AA made it into UE?) do I need B3 for the smaller gecko?

[Eric Brittain]

If you want to use something you must:
A) Have the documentation that proves it is legal (Additional resources)
B) Have all of the source material it comes from (physical book or watermarked PDF. Website copy does not count as 'having the material'). This can mean that you need to have both a copy of the book that shows that you can buy it as well as the appropriate bestiary that has its stats.
C) Be able to produce both A and B above to your table GM when requested

[Lady Ophelia]

TLDR Answer: Yes. Buta Watermarked PDF will be just as acceptable as hardcover. (Can't beat a 10 dollar PDF.)