Rewindykacja dóbr kultury. msz.gov.pl. [zarchiwizowane z tego adresu (2012-08-03)]. at Polish Ministry of Foreign Affairs, dostęp 2014-06-09 z archiwum web.archive.org.
JudithJ.Olsak-GlassJudithJ., Review of Piotrowski’s Poland’s Holocaust, „Sarmatian Review”, styczeń 1999 [dostęp 2008-01-24], Cytat: „The prisons, ghettos, internment, transit, labor and extermination camps, roundups, mass deportations, public executions, mobile killing units, death marches, deprivation, hunger, disease, and exposure all testify to the 'inhuman policies of both Hitler and Stalin’ and 'were clearly aimed at the total extermination of Polish citizens, both Jews and Christians. Both regimes endorsed a systematic program of genocide.”(ang.).
Rewindykacja dóbr kultury. msz.gov.pl. [zarchiwizowane z tego adresu (2012-08-03)]. at Polish Ministry of Foreign Affairs, dostęp 2014-06-09 z archiwum web.archive.org.