This is the full report made by the Auschwitz escapees Rudolph Vrba and Albert Wetzler. This is their account of what they witnessed during their time there, as best a record of the numbers murdered, who the victims were and the perpetrators that they could recall. Content warning; graphic content.
The biography of one of the authors of the report is here: https://libcom.org/history/rudolph-vrba-escapee-auschwitz-anthony-skelton-carmelo-lisciotto
It is important that atrocities are exposed to the light of day so that they cannot be denied or downplayed.
This PDF is a combination of all 3 parts of the report found on www.HolocaustResearchProject.org.