No, I'm not a holocaust denier. Good grief!
My source is my ability to read and reason logically. How hard is it to understand that since Adolph Hitler was not the chancellor of Germany until January 30, 1933, therefore none the actions described as taking place in "the first few weeks of 1933" could have happened until a minimum of January 31st, 1933. It's just common sense.
However, I checked my copy of "Rise and Fall of the Third Reich" written by William L. Shirer, an American journalist that lived in Germany during the 30's and 40's. The book is considered one of the definitive works on the history of Nazi Germany.
The purge of opposition newspapers did not happen until after the Reichstag fire of February 27, 1933. On February 28, 1933 while in emergency session, the German legislature passed "The Decree of the Reich President for the Protection of the People and the State". This allowed imprisonment of political opponents and the trashing of the opposition press.
Oh my...I just looked up "The Decree of the Reich President for the Protection of the People and the State" on your Holocaust site and it claims it occurred on February 4, 1933! Just an astonishing error!