F1-Mischbereifung does not permit

In the formula it is not permitted to 1 to install in front and in the back differently hard rubber mixtures. Excitement prevailed on Friday with free training to the Turkey Grand Prix, when Williams pilot was Nico Rosberg with two tires on the test track, which were to be recognized by a white marking as softer, while the other two tires were not marked. After an investigation of the tires it turned out however that it had quite concerned a complete tire set, however two of the four tires by Bridgestone by the circulating white volume had inadvertently not been marked.