1. Go to https://www.behindthename.com/top/; 2. Once there, click on a country's name (e.g. United States); 3. The source is mentioned at the very top of the page, which in the case of the United States is the Social Security Administration (SSA).
Forchta in biuonga quamon ouer mi, in bethecoda mi thuisternussi. In ic quad: "uuie sal geuan mi fetheron also duuon, in ic fliugon sal in raston sal?"