Curious Variables Experiment (CURVE). CCD Photometry of Dwarf Nova V660   Herculis
  We report extensive photometry of the dwarf nova V660 Herculis. During our campaign, lasting from August 2003 to November 2004, we recorded one bright eruption which turned out to be a superoutburst lasting about 15 days and having amplitude of ~4.5 mag. Clear superhumps with a mean period of Psh = 0.080924(18) days were present during all nights of the superoutburst. The period of the superhumps was not stable and in the interval covered by our observations it decreased with a rate of -4.0(1.4) * 10^{-5}.   Basing on our data and the known orbital period of the binary (Thorstensen and Fenton 2003) we calculate the period excess of 3.4 +/- 0.1%, which is typical for an SU UMa star at this orbital period. This value indicates that the mass ratio of the system is q=0.154. 
A. Olech, K. Zloczewski, L.M. Cook, K. Mularczyk, P. Kedzierski and M.   Wisniewski