During the 1970s and 1980s, Criss Library purchased a number of microfilm collections containing declassified documents that originated with the U.S. State Department and the Central Intelligence Agency. Some of the documents may be accessible online at the electronic reading rooms of the CIA and State Department, but the microfilm collections are typically more comprehensive.
You can find indexes to the microfilm collections shelved in the bookcase near the newspaper microfilm cabinets on the 1st Floor. The microfilm reels for these declassified documents collections are shelved along the far western wall of 1st floor. The call numbers assigned to the indexes are the same as those assigned to the microfilm reels. If your interest pertains to Cold War developments in a particular country or region, you may find browsing the indexes a helpful way to identify a cluster of pertinent primary sources.