@47th_President
If any American citizens who collect retirement, ssi or ssdi need their proof of income certified by the Apostille, they will not be able to obtain the letter signed, with the employees name and their title. In my opinion this is a waste of time.

There is a much easier way to have these documents certified. As long as it is not signed you can take it to a local notary public and have it notarized as a copy.

Then take it to the Apostille at your local secretary of state's office where they will certify for the specific country according to the Hague convention in a matter of minutes.
The other option is to mail it in with a signature and they won't do it. I tried and failed twice.