Books can be attributed to "Unknown" when the author or editor (as applicable) is not known and cannot be discovered. If at all possible, list at least one actual author or editor for a book instead of using "Unknown".
Books whose authorship is purposefully withheld should be attributed instead to Anonymous.
His caption of taking a photo of Joseph Goebbels, Nazi minister of propaganda, says:
“This picture could be titled ‘From Goebbels with Love.’ When I went up to him in the garden of the hotel, he looked at me with hateful eyes and waited for me to wither. But I didn't wither. If I have a camera in my hand, I don't know fear.”
A marvelous book of photographs from the great German photographer Alfred Eisenstaedt, all of his native country, spanning 1913 to 1980. Eisenstaedt fled Germany in 1935 for the West, during the Nazi era, and photographs people as diverse as Gunter Grass, Joseph Goebbels, Lufthansa stewardesses and chimney sweeps during 50 years of German history. He likes to contrast Germany of the '20s and '30s with the informality of Berlin in the late '70s and early '80s.