O'Brien, M. J. (1930). An alleged first census of the American people: A criticism of William M. Clemens' book, "American marriage records before 1699". New York: [s.n.].

O'Brien, Michael Joseph. An Alleged First Census of the American People: A Criticism of William M. Clemens' Book, "American Marriage Records Before 1699". New York: [s.n.], 1930.

O'Brien, Michael Joseph. An Alleged First Census of the American People: A Criticism of William M. Clemens' Book, "American Marriage Records Before 1699". New York: [s.n.], 1930.