Charles Hodge: Commentary on the Epistle to the Romans
- Theological treatise and commentary by Presbyterian theologian who taught at Princeton Theological Seminary. Written 1864, 716 pages. (Image, text, PDF)
- http://quod.lib.umich.edu/cgi/t/text/text-idx?c=moa;idno=AGA1502

An Exposition of the Epistle of Saint Paul to the Romans
- By Morgan Dix (1827-1908), an American Episcopal minister. Verse commentary published in 1863 (Image, text, PDF).
- http://quod.lib.umich.edu/cgi/t/text/text-idx?c=moa;idno=AJH0281

Moses Stuart: A Commentary on the Epistle to the Romans
- Congregationalist minister and Professor at Andover Seminary. Published in 1854. (Image, text, PDF)
- http://quod.lib.umich.edu/cgi/t/text/text-idx?c=moa;idno=AJH0296

Romans: The Gospel of God's Righteousness
- By Greg Herrick. Introduction, analysis of Paul's presentation, and exposition.
- http://www.bible.org/series.php?series_id=22

The Epistle of St. Paul to the Romans
- By Allen Ross.
- http://www.bible.org/series.php?series_id=110

Notes on Romans
- Commentary, by Jeff Asher, in outline form covering the entire Book of Romans.
- http://www.bibletalk.net/acrobat/romans-notes.pdf

Romans Verse-by-Verse
- By William Newell.
- http://www.ccel.org/ccel/newell/romans.html

Romans Chapter 5
- Excerpt from commentary by Charles Hodge.
- http://www.reformed.org/books/romans/rom_5a_hodge.html

Matthew Henry's Commentary on the Whole Bible: Romans
- Commentary published in 1721 which looks at biblical passages paragraph by paragraph.
- http://www.ccel.org/h/henry/mhc2/MHC45000.HTM

Martin Luther: Preface to Romans
- Contains the preface to Luther's commentary (text, html).
- http://www.ccel.org/l/luther/romans/