That is how I got it, but I believe it is also available in hard cover.
Both are available at Amazon.
When I want use a book as reference or to re read, I use Kindle.
I have Kindle on my desktop pc computer.
Also, I have Kindle Cloud on my Acer Chromebook 15, which I am using now, and my Acer Tablet.
One purchase covers all of the above three user sites.