P.-ST, A. De forenede Staters Census-Arbejder. Publications of the American Statistical Association. Boston, 1888. New Series Nos. 1, 2. 3. Nationaløkonomisk Tidsskrift, [S. l.], v. 7, 1889. Disponível em: https://tidsskrift.dk/nationaloekonomisktidsskrift/article/view/65437. Acesso em: 10 maj. 2024.