There are a lot of good things that you can access for free at Gallica, a digital text archive of the Bibliothèque National de France. Two years ago I reported that the first 14 volumes of the Archives d’histoire doctrinale et littéraire du Moyen Âge are available there.

A month or so ago I discovered that you can also access all of the volumes of the Revue thomiste from 1893 to 1936 at Gallica. This is incredibly useful. Go here for the complete listing of the available volumes.

While you're there, you might want to spend a little time exploring the rest of Gallica to see what other treasures it yields.

UPDATE: I just realized that there are some gaps in the Revue thomiste volumes at Gallica. Three of those gaps (1915, 1916, 1917) I assume are due to suspension of publication during a part of World War I. I don't know what the explanation is for the other two gaps (1920, 1926). I had originally put "first 39 years" in the title of this post. 39 is the actual number of years that Gallica has volumes for between 1893 and 1936. 43 is simply the number of years between 1893 and 1936. I've decided to go with 43 but with the qualification about the gaps that I mention in this update.