The Divine Comedy - Paradise by Dante, translated by Dorothy Sayers and Barbara Reynolds. 1962, ISBN 0140441050.
The Divine Comedy - Paradise by Dante translated by Charles Eliot Norton. 1892, PDF from books.google.com.
This is the third and final volume in Dante's poetic description of a journey through the three realms of the afterlife. In this volume Dante enters paradise, the heavens of crystalline spheres that surround the earth. There he meets various Saints who enlighten him concerning the nature of the divine and salvation. Dante's universe was the Ptolemaic system where the Earth was at the center and the Planets (wanderers, Moon, Mercury, Venus, Sun, Mars,  Jupiter, Saturn ) and stars occupied various crystalline spheres that rotated above the Earth.  
The Sayers translation was purchased back in the 1970's for 90 cents, probably from a book store near PSU. The Norton translation was a .mobi file (3ddcn10.mobi) a project Gutenberg book downloaded from the internet. Also, can be found at books.google.com.

The Divine Comedy - Purgatory by Dante Alighieri, tr Dorothy L. Sayers, 1955, ISBN 0140440461. The Divine Comedy - Purgatory tr Charles Eliot Norton, 1891.

The Sayers translation was an actual book. Probably purchased in 1973, for $1.05, maybe at Powells, maybe at a bookstore by PSU. This translation has a long introduction and notes after each canto. Plus there are several Appendix that discuss certain issues in more detail. In the Divine Comedy Dante mentions many people and scholars have tried since it was first made available to determine who these people where. Matilda is one such character who has be speculated about for many years. This translation is again in verse form, that tries to reproduce the Italian Terza rima.

The second translation I read was the Charles Eliot Norton. This is a file I read on my kindle (2ddcn10.mobi), which can be found at websites that have public domain texts. I think this was originally a project Gutenberg text (here.) This translation is older and in prose form. It also has notes to explain the various references.

The Divine Comedy: Hell by Dante Alighieri, translated by Dorothy L Sayers. 1949, ISBN 0 14 044 006 2.

The Divine Comedy: Inferno By Dante Alighieri, translated by Charles Eliot Norton. 1891.

The Sayers translation was the actual book. I purchased it probably in 1973. This is the third time I have read it. The Norton translation is an ebook (1ddcn10.mobi, it is a Gutenburg text, google it.) I don't remember where I downloaded it from, but it is in the public domain.
I read these two translations canto by canto. Sayers tried to translate into English the poetic form of the original Italian. She discusses it in the introduction. Norton is a prose translation. Both have notes to explain various references, but Sayers are much better (of these two.)

This is a story that takes place in medieval Italy. It is about a lost soul (Dante) searching for the truth. Hell is populated with many famous people, some real and some fictional. Also, there are many people that Dante knew, but who are unknown today.