«Review of A Treatise on the Circle and the Sphere (1971 reprint)», Mathematical Reviews, MR0389515
doi.org
dx.doi.org
H. P. H. (dezembro de 1916), «Review of A Treatise on the Circle and the Sphere (1916 edition)», The Mathematical Gazette, 8 (126): 338–339, JSTOR3602790, doi:10.2307/3602790
White, H. S. (julho de 1919), «Circle and sphere geometry (Review of A Treatise on the Circle and the Sphere)», American Mathematical Society ({AMS}), Bulletin of the American Mathematical Society, 25 (10): 464–468, doi:10.1090/s0002-9904-1919-03230-3
jstor.org
H. P. H. (dezembro de 1916), «Review of A Treatise on the Circle and the Sphere (1916 edition)», The Mathematical Gazette, 8 (126): 338–339, JSTOR3602790, doi:10.2307/3602790