After ending his active career, Nielsen was a sports journalist for Aftenbladet, Politiken, and B.T., and wrote two books about football.
Piet Hein's gruks first started to appear in the daily newspaper "Politiken" shortly after the Nazi Occupation in April 1940 under the signature Kumbel Kumbell.
Politiken reported that the Danish government had protested to Germany, pointing out that the E13 had not been destroyed in any kind of pursuit but while she was lying damaged on neutral territory.
The Danish Department of Defense tried to suppress its publication, but the Danish newspaper Politiken published it as a supplement to its September 15 issue.
The Danish music magazine Gaffa and two national papers, Politiken and Ekstra Bladet, wrote that Sneglzilla was the best album of 2002, and it won two Danish Music Awards, two Steppeulve and six prizes at the Danish Hiphop Awards.
He has worked for several TV stations as a commentator and recently as a football columnist from January until June 2007 with Danish newspaper Politiken.
Dagbladet Politiken (The Daily Politiken) was founded on 1 October 1884 in Copenhagen by Viggo Hørup, Edvard Brandes and Hermann Bing.
The Danish Ministry of Defence tried to stop the publication of the book, but on September 15, 2009, the Danish newspaper Politiken published the book in full as part of the newspaper.
He is also widely published in newspapers and magazines including the International Herald Tribune, New York Times, Time, Sydney Morning Herald, Financial Times, Singapore Straits Times, Die Welt and Politiken.
Persson has supplied photos to Down Beat since 1962, Jazz Special (DK), Musica Jazz (IT), Melody Maker (UK) and Danish newspapers Politiken, Berlingske Tidende and Ekstra Bladet.
From 2004 to 2006 he worked as a staff photographer for the Danish newspaper Politiken, and subsequently as a freelance photojournalist for newspapers such as Newsweek, TIME, Der Spiegel, Stern or Sunday Times.