Canada Month, June 1963. A later satirical version of this saying added to the end "Luckily, this is not difficult" (Paul Dickson, The Official Rules [1978]). See Eleanor Roosevelt 2
Elizabeth Cady Stanton (2003). “The Selected Papers of Elizabeth Cady Stanton and Susan B. Anthony: National protection for national citizens, 1873 to 1880”, p.491, Rutgers University Press