1. Powder Diffraction File . International Centre for Diffraction Data, 12 Campus Blvd., Newtown Square, PA 19073 3273
2. Crystal Data File . International Centre for Diffraction Data, 12 Campus Blvd., Newtown Square, PA 19073 3273
3. The theory of X-ray reflexion;Darwin;Philos. Mag. [6],1914