UPDATE: I WAS WRONG. See the comments.
Don't you wish the Library of Congress had a subject heading for Critical Mass (the nearly 20-year-old internationally celebrated monthly bike ride)? Me, too!
So I wrote to the Library of Congress:
I recommend adding terminology for http://id.loc.gov/authorities/subjects/sh85035075 "Cyclists--Political activity" (from Critical mass: bicycling's defiant celebration http://lccn.loc.gov/2006295270 ): Critical mass (Cycling) --or whatever you think is appropriate in the parenthetical. If it gives him some credence, the author, Chris Carlsson has six other items in your catalog. I see you have another item in your catalog that would serve as a good warrant: http://lccn.loc.gov/2009048506.
I'm prompted to request the addition right now because it would be appropriate for issue no. 2 of Ker-bloom! : on death & dyar. http://clio.cul.columbia.edu:7018/vwebv/holdingsInfo?bibId=9129759 (I don't have an abstract for it yet to explain the connection to Critical Mass, but be assured, Artnoose does discuss it in 20% of the content.)
PS Thanks for Dumpster diving, from month 25!