Volker published a great overview of the time he and Hammer spent together in Italy called, Hammertime in Europe. Volker is one of the worlds leading authorities on all things Vintage Panerai, and co-authored many definitive Panerai history books. You can learn much more about Volker on his excellent VintagePanerai.com website.
You can learn much more about Hammer by checking out this story I wrote about him named Hammer Strength. Hammer is one of the leading, if not the leading vintage Panerai collectors in the world, and he owns what is arguably the most beautiful Panerai in existence, which is the Reference 6154, as seen below on the left, next to his Reference 6152 on the right.
While at the new Panerai factory, Volker took the photo of the all-new Panerai PAM 587 Marina Militare pictured below.