1941 Original model Sheet Captain America and Bucky
As documented in Joe Simon's, The Comic Book Makers, after creating the first issue of Captain America, Simon and Kirby formed their own studio moving into a small space, hiring additional artists, embarking on their way to immortality.
As a guide to everyone concerned, Simon created a model sheet depicting Cap and Bucky, noting the changes in costume, shield and relative size of the characters. Four pin holes demonstrate how the model sheet was exhibited in the "studio".
On the back Joe notes his home address at the time "Haddon Hall" located in Morningside heights at Columbia University where Joe had first settled after moving from Syracuse to Manhattan.