International
Tables for
Crystallography
Volume C
Mathematical, physical and chemical tables
Edited by E. Prince

International Tables for Crystallography (2006). Vol. C. ch. 9.2, p. 755

Figure 9.2.1.7 

D. Pandeyc and P. Krishnab
[Figure 9.2.1.7]
Figure 9.2.1.7

A rhombohedral lattice (a1, a2, a3) referred to hexagonal axes (A1, A2, C)(after Buerger, 1953[link]).