The Challenges of Researching the Victims of Auschwitz

Many of the people who became prisoners of Auschwitz were later transported to other camps and research on their fate is another challenge. It was much easier to say how many perished immediately upon the arrival in the gas chambers, because these people were not registered in the camp. There are many matters to estimate the number of prisoners who were registered and who were killed in Auschwitz. How many escaped from Auschwitz? How many were liberated? The side, the Russian forces in entry and what is more important, how many Auschwitz prisoners were transferred to the other camps in Germany?"