Written between 1147 and 1150, these four books are what made Lombard famous. They are a long series of questions and answers in which Lombard addresses just about everything that the teachings of theology could address. More importantly, it is a systematic theology. An important aspect of this work is the numerous sources it cites, particularly from the various Latin Church Fathers. Many questions are left open-ended. Many commentaries on the Sentences, notably by Thomas Aquinas, carry on the discussion.
Book 1--The trinity Book 2--Creation, both spiritual and physical things Book 3--Incarnation Book 4--Sacraments
The artifact I found is a partial translation. The authors have completed Book 1 and part of Book 2. Scroll part way down the page and you can find links to those. Additionally, you can find links to many commentaries on the Sentences at this website. http://www.franciscan-archive.org/lombardus/
Book 1--The trinity
Book 2--Creation, both spiritual and physical things
Book 3--Incarnation
Book 4--Sacraments
The artifact I found is a partial translation. The authors have completed Book 1 and part of Book 2. Scroll part way down the page and you can find links to those. Additionally, you can find links to many commentaries on the Sentences at this website. http://www.franciscan-archive.org/lombardus/
Sources:
Catholic Encyclopedia: http://www.newadvent.org/cathen/11768d.htm
Internet Encyclopedia of Philosophy: http://www.iep.utm.edu/lombard/