Just one piece and it's on the small side. After the long readings of the past few months, it will be nice to have a short one.
St Thomas Aquinas: Summa Theologica (part One of the Second Part Questions 90-97) link
This may win the award for the most confusing and hard to find section. If you're looking in the actual Great Books, it's in Volume 20, pages 205-239. The title is 'Treatise on Law' and it goes from Question XC through Question XCVII (or 90-97, if the Roman numerals give you fits).