https://steidl.de/Books/Philippe-Halsman-A-Photographer-s-Life-0009212241.html
https://steidl.de/Artists/Henry-Leutwyler-1317293853.html?SID=JOu1AVrd4923
https://www.esquire.com/entertainment/books/a32766621/frank-sinatra-phone-book-henry-leutwyler-hi-there/
https://www.wsj.com/articles/inside-frank-sinatras-personal-address-book-11591101340