Committee Prints: Research reports prepared by committee staff, consultants, the Library of Congress, and others. Committee prints are issued in numerical order by each chamber of Congress. They usually contain material prepared by committee staff for the use of the committee considering the bill.
Bluebook Rule 13.4 (c)
"Unnumbered federal documents and committee prints. Committee prints and unnumbered documents must be cited as works of institutional authors (rule 15.1(c)). Note that the number of the Congress is part of the author's name:. If the document or committee print is primarily the work of specific persons, that fact may be noted parenthetically."
Example
Staff of S. Comm. on Homeland Security and Governmental Affairs, 113th Cong., Rep. on Defense Acquisition Reform: Where Do We Go From Here? A Compendium of Views by Leading Experts 28 (Comm. Print 2014).
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