That is 3A (postcard) format, which would have been shot on 122 rollfilm. 3A was 3.25" x 5.5" image size, which translates to 82.5mm by 139.7mm. The film stock is 91.75mm wide. Kodak discontinued that size in 1974, more or less, but there's gonna be more of it in September... (see this thread).
Originally Posted by winger