Golden Era correspondence with printed logos on them are always nice to find when I visit the Finnish National Archive. The logo is always located on the top left hand corner of the paper (usually an A4). It contains the full name of the company along with its address and the telephone number(s). These are always done with a typing machine and usually signed with black ink, although ones signed with blue ink can be also found.
All of the following examples are from year 1937.