Which difficulty?
In Lunatic, both those attacks are considered awesomely hard. Do not be embarrassed to bomb them.
In other difficulties, I could only beat the green books after being able to beat the difficulty above (so, could only clear the normal ones perfectly after 1ccing hard mode, etc) and I've never faced Emerald Megalith so can't really comment.
I don't think there's any real strategy.
Oh, for the books, if they all spawn on one side of the screen, go to the other side.
...You probably do that anyway >_>