International
Tables for Crystallography Volume H Powder diffraction Edited by C. J. Gilmore, J. A. Kaduk and H. Schenk 
International Tables for Crystallography (2018). Vol. H, ch. 3.1, p. 228
Figure 3.1.8^{a}National Institute of Standards and Technology, Gaithersburg, Maryland, USA 

Figure 3.1.8
Axial divergence aberration profiles shown for several levels of axial divergence. Case 1 (of Table 3.1.1) is computed for a source length of 12 mm and a sample and receivingslit length of 15 mm. The remaining three simulations include are of case 2, where Soller slits limit the axial divergence (R = 217.5 mm). 