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The dwarf nova CG Dra was intensively monitored during 2005 as part of the Variable Star Sections Recurrent Objects Programme and seven outbursts were detected. These observations were combined with others from the BAA and AAVSO databases which confirmed that the star shows frequent outbursts with a period of around 11 days. Two types of outburst have been detected. Short outbursts lasting about 4 days and long outbursts lasting about 8 days.

I use integral field and long-slit spectra from the AAT and the Magellan telescope to investigate the kinematics of several clumps, recently identified along the prominent tidal tail of CG J1720-67.8 and suggested as possile tidal dwarf galaxy (TDG) candidates. A comparison of photometric and spectroscopic data with evolutionary synthesis models suggests burst ages of ~ 6 Myr for these clumps/TDG candidates.

A finite group $G$ is a CG-group if $|{\rm Cent}(G) | = | G' |+2$, where $G'$ is the commutator subgroup and Cent$(G)$ is the set of distinct element centralizers of $G$. In this paper we give some results on CG-groups. We also give a negative answer to \cite[Conjecture 2.3]{con} given by K. Khoramshahi and M. Zarrin.