International
Tables for Crystallography Volume B Reciprocal space Edited by U. Shmueli © International Union of Crystallography 2010 
International Tables for Crystallography (2010). Vol. B, ch. 2.5, pp. 315317
Figure 2.5.3.7
M. Tanaka^{f}


Figure 2.5.3.7
Illustration of symmetries appearing in hexagonal sixbeam, square fourbeam and rectangular fourbeam darkfield patterns expected for all the diffraction groups except for 1, 1_{R}, 2, 2_{R} and 21_{R}. 