International
Tables for Crystallography Volume H Powder diffraction Edited by C. J. Gilmore, J. A. Kaduk and H. Schenk © International Union of Crystallography 2018 
International Tables for Crystallography (2018). Vol. H, ch. 1.1, p. 20
Figure 1.1.25^{a} 

Figure 1.1.25
Flow diagram of a simulatedannealing procedure used for structure determination from powder diffraction data (from Mittemeijer & Welzel, 2012). F in the double sum is the structure factor from the structural model at each step of the optimization. Each sum runs over all reflections. h and k are summation indices representing hkl and h′k′l′, respectively. 