Lei Wang, Yu Sasaki, Wataru Komatsubara, Kazuo Ohta, and Kazuo Sakiyama, “(Second) Preimage Attacks on Step-Reduced RIPEMD/RIPEMD-128 with a New Local-Collision Approach,” In Proc. RSA Conference 2011, Cryptographer’s Track (CT-RSA’11), LNCS 6558, Springer-Verlag, pp.197–212 (Mar., 2011).