How about this part of his post?
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In my thesis, I attacked coinmixer.se (at the time of writing it was the biggest centralized mixing service), however - except chipmixer.com1 - every other centralized mixing service I checked could be broken in a similar fashion.
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1 Chipmixer was the only centralized mixing service which I did not break fully. However, I did not put much work into checking this mixing service.