By Museum Ludwig Cologne
By Lehnert, Gertrud
By Dalton, Patrick
By BHB International
By Angelika Taschen
By Wannenburgh, Alf, Johnson, Peter, Bannister, Anthony
By Unesco's World Heritage Committee
By George Wayne
By Bertolazzi, Alberto
By Coulter, John
By Elffers, Joost, de Vries, Mirja
By Rhem, James, Siskind, Aaron
By Bullock, Wynn
By Krase, Andreas, Adam, Hans-Christian, Atget, Eugene
By MODEL, Lisette
By Turner, Professor of English Language and Literature Mark
By Boot, Adrian, Salewicz, Chris
By National Geographic
By Lonely Planet
By Hyland, Angus, Farrelly, Liz
By Hugh Palmer
By Graham, David
By VICTOR BURGIN
By Wood, David
By Muir Richard
By Bayon Publishing
By Middleton, David, Fortney, Bill, Kuralt, Charles
By Angela Rippon, Derry Brabbs
By Runtz, Michael
By Beals, Sharon