Get a
free copy (or copies, if you choose to download more than one format) of John Piper's
This Momentary Marriage. This ebook comes courtesy of the publisher Crossway.
The ebook is about 190-195 pages long. To get the
"free" ebook, you must fill out a "brief survey." This particular survey takes more thinking to honestly and accurately complete than a lot that we've come across; at least it did for me. You had better count on spending about 15 minutes on it.
I mentioned that you would be able to download more than one format. Those are mobi, ePub, and PDF.
This webpage tells you probably everything else that you need to know.