Bibliographies are my thing. I haven’t read all of these, but I am in the process of doing so. There is more to the Reformed faith than Calvin. Calvin is good and writes better than most, but he wasn’t anything special back then. Bullinger outsold Calvin and Perkins outsold all combined.
Sadly, little of these writings were ever translated, with the result that classical Protestantism was reduced to the 5 Points.
Turretin, Francis. Institutes of Elenctic Theology. Start here. Turretin teaches you how to think.
Ames, William. Marrow. I disagree with Ames’s voluntarism, but this was the most important theological text to make it to America.
Witsius, Herman. Economy of the Covenants. This will guide you through issues on the Federal Vision, Kline, etc.
Clark, R. Scott. Caspar Olevianand the Substance of the Covenant. Any doctrine that denies the inner/outer distinction of the covenant isn’t Reformed.
Rutherford, Samuel. Trial and Triumph of Faith. Good defense of the Pactum Salutis.
Books I’ve Yet to Read
These are on my list.
Cocceius, Johannes. Doctrine of the Covenant and testament of God.
Heidegger, Johannes. Concise Marrow of Theology.
You can’t speak on Reformed Scholasticism unless you can intelligently speak on these works.
Preuss, Robert. Post-Reformation Lutheranism. The Lutheran version.
Oberman, Heiko. The Harvest of Medieval Theology. Look closely and you can tie in the Federal Vision.