The most complete set available of the writings of the Princeton theology professor known for his precise Calvinistic scholarship, keen logic, and spiritual insight.
Benjamin Breckinridge Warfield (usually known as B. B. Warfield) was professor of theology at Princeton Seminary from 1887 to 1921. Some conservative Presbyterians consider him to be the last of the great Princeton theologians before the split in 1929 that formed Westminster Seminary and the Orthodox Presbyterian Church.
This is an excellent reference set, one which I highly recommend. The volumes on Revelation & Inspiration and Perfectionism are probably still the best that can be found on these important subjects.