Hi, many thanks for your interest and your time...
Carlosfaro: As far I know, at list at their first combat actions when trying to release the fascist pressure over Madrid, the soviet tanks were commanded and crewed by Russians. Even at the time of the Teruel's battle, quite latter on the war, Ernest Hemingway wrote about the lack of fighting spirit of the soviet crews who were at the last weeks of their turns and tried to avoid being killed or wounded so close to their return home. But in fact, most probably, the Russian writings came from the factory and was made by the workers who build the tanks.
In accuracy terms, most of the Republican tanks wore not tactical signs. Some of them had some numerals portrayed on the turret's sides or rear. The reason why I put some signs on them is just to identify them as a Republicans and because some of the crews could have painted their vehicles that way. But it was not the norm and most of the period's pictures did'nt show any tactical sign at all.
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