hydrogenchloride in hydrogenchloride dissolving Ru(OH)4 in HCl (100°C), addn. of H2C2O4; according to Shorikov, Yu. S., et al., Zh. Neorg. Khim., 1984, 29(12), 2999; (Russ. J. Inorg. Chem., 1984(12)); evapn., drying (vac. over alkali, room temp.); elem. anal.;