Wielka Encyklopedia Powszechna PWN

As is stated in the foreword, the encyclopedia is "based on rationalist and materialist assumptions" and reflects the worldview of the "socialist ideology".

About 2000 authors, 1000 reviewers, and almost 100 editors were supervised by the Scientific Board appointed by the Polish Academy of Sciences (PAN) and the Ministry of Higher Education, and headed by Professor Tadeusz Kotarbiński.

The initiative to write the WEP was taken by PWN in July 1957 when it was decided that an 8-volume (later expanded to 12 volumes) universal encyclopedia would be published.

with dates of publishing: Volume 8 includes an article entitled "Hitlerite concentration camps" (Obozy koncentracyjne hitlerowskie) which caused much controversy.

The major objections were that: As the result, the editorial team was "renewed" and a new, revised article, this time entitled "Hitlerite camps" (Obozy hitlerowskie), was added as an inset to Volume 11, and later included in the Supplement.