International Tables for Crystallography (2006). Vol. A. ch. 4.2, p. 61
https://doi.org/10.1107/97809553602060000508

Chapter 4.2. Symbols for plane groups (two-dimensional space groups)

Chapter index

Additional symmetry elements 4.2.2
C and c cell (tetragonal and hexagonal lattices) 4.2.3
Extended Hermann–Mauguin space-group symbols 4.2.1.1
Hermann–Mauguin
plane-group symbols 4.2.1, 4.2.1.1
symbols, changes of 4.2.1
Hexagonal
plane groups 4.2.1.1
Oblique plane and point groups 4.2.1.1
Plane (two-dimensional) space groups 4.2.1, 4.2.1.1
symbols for 4.2.1, 4.2.1.1
Rectangular plane and point groups 4.2.1.1
Square plane and point groups 4.2.1.1
Symbols
for plane (two-dimensional) groups 4.2.1, 4.2.1.1
Symmetry
elements, additional 4.2.2
Two-dimensional (plane)
lattices, nets and cells 4.2.1
space groups 4.2.1
space groups, symbols for 4.2.1, 4.2.1.1