the bbc's olga ivshina has been investigating russian casualties since the start of the full-scale war, and i asked her to tell me more about how the information is gathered and verified. all our data, all our data are based only on open sources, and only on sources confirmed by the russian side. we do this on purpose. so that the numbers we have now would be impossible refute, because these are official statements of russian persons, publications of close relatives and friends on social networks, we check all publications on social networks, and there is also data from military memorials and cemeteries, this is not the largest segment, but it is very important, because it allows us to understand not only how many names we have, but also how many names we are losing, because every time we get information from some war memorial, monument, cemetery, we see... all those soldiers whose deaths were announced publicly , and plus from 30 to 70% of those about whom not publicly stated, but here is evidence that they died, so that's it... we think that we can add about the same number to our da