1. W. L. Bragg, Proc. Roy. Soc. (Nov. 1913). [Vol. I. paper 17]
2. Hull, Phys. Rev. (10 Dec. 1917).
3. * [Note the weak point in the following deduction, no distinction being made as to the type of bonding of the particle, see this Vol. p. 43 and paper 117. Ed.]
4. Ewald, Phys. Zs. (April 15, 1914). [Vol. I. paper 18]
5. Acta Soc. Scient. Fennicae50 No 2 (1920).