The first one is from 1938 to Germany. Most machine postmarks are from Buenos Aires. This is a rare instance of a machine postmark from a neighborhood of Buenos Aires (Coghlan), instead of the more common use of the post office number, such as it would have been by using Buenos Aires 30.
The second cover is from 1939 to the US.
The third cover is from 1942, also to the US. Notice the use of paper tape for the censorship instead of the (later) use of plastic tape.
