Michel Velleman (5 January 1895 – 2 July 1943),[1] known by his stage name Professor Ben Ali Libi, was a Dutch magician who was murdered in the Sobibor extermination camp during World War II.

[2] Velleman was a well-known magician, performing for notables such as the Dutch prince consort and the exiled German Emperor Wilhelm II.

[4] Velleman and his wife Anna (née Speijer) were living in Amsterdam when they were abducted during a razzia on June 2, 1943.

The penultimate verse of the poem reads in English translation:And always when there’s a shouter to see with an alternative for democracy I think: your paradise, how much space is there

[4] In 2015, Velleman was the subject of a Dutch documentary film titled Ben Ali Libi, Magician, directed by Dirk Jan Roeleven.