A Sandburg Stumper

[Rob Wick]

Try to answer this without looking it up. The University of Illinois at Champaign-Urbana holds the largest collection of Sandburgiana in the world. However, it ranks third in the number of collections that has material related to Sandburg. In other words, while it has the largest collection of Sandburg material by volume in its collection, there are two other facilities that, while not having the total number of papers, has more collections that has material related to Sandburg. What are the first and second?

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Rob