AP world history book?

<p>Hi guys,</p>

<p>I am going to take the sat world history subject test in June, so in one month.
My preparation starts now and I have the Barrons Sat world history book at home as well as the PR one. However, I do not take AP World history and a lot of people say that it is recommended, as the test is kinda based on the AP WH course. My question: Is is enough to use the two books mentioned above or is it a must that I buy the AP WH book for a more detailed review. I, obviously, want to get an 800 and since there is only one month left, I was wondering if I absolutely need the AP WH Book (it's long) to get that score or if the two mentioned books are absolutely enough.
Any advice?</p>