# Categories

- A
- Algebraic Curves and Surfaces
- B
- Combinatorical Geometry
- I
- Configurations
- II
- Regular bodies und crystals
- Tetrahedron-, octahedron-, icosahedron-division on the spherical surface
- Tetrahedron-, octahedron-, icosahedron-division on the spherical surface
- Tetrahedron-, octahedron-, icosahedron-division on the spherical surface
- Grid of the diamond and the corresponding sphere packing
- Grid of the diamond and the corresponding sphere packing
- Structural model of the diamond
- Grid a) of the diamond, b) (by distance of the diagonal bars)
- 24 stereo's of crystal lattices with text volume
- Stereo: pentagonal dodecahedron with 5 inscribed dice
- Kreutz: Elements of the crystal structure
- Model of the thinnest ball bearing (diamond grid)
- Grid of the wurtzite and the thinnest ball bearing
- Dodecahedron with the 5 inscribed cubes
- Cube and inscribed octahedron
- Regular tetrahedron, hexahedron, octahedron, icosahedron
- Thinnest ball bearing of the coordination number 4
- Ball bearing
- Ball bearing (diamond grid)
- Thinnest ball bearing
- Ball bearing
- Thinnest ball bearing
- Prismatic polygon with n vertices
- Saw-border polygon with n vertices
- Tetrahedron with inscribed truncated tetrahedron
- Octahedron with inscribed truncated octahedron
- Octahedron with inscribed cuboctahedron
- Octahedron with inscribed snub cube
- Cube with inscribed rhombicuboctahedron
- Truncated cuboctahedron
- Icosahedron with inscribed truncated icosahedron
- Dodecahedron with inscribed truncated dodecahedron
- Dodecahedron with inscribed icosidodecahedron
- Icosahedron with inscribed icosidodecahedron
- Rhombicosidodecahedron
- Snub dodecahedron
- Octahedron
- Tetrahedron
- Icosahedron
- Four surface models to the illustration of elastic coefficients of extension
- Four surface models to the illustration of elastic coefficients of extension
- Four surface models to the illustration of elastic coefficients of extension
- Four surface models to the illustration of elastic coefficients of extension
- Glass crystal model according to Schnabel
- Glass crystal model according to Schnabel
- Glass crystal model according to Schnabel
- Glass crystal model according to Schnabel
- Glass crystal model according to Schnabel
- 5 models of intermediate forms
- Model of an intermediate form
- Model of an intermediate form
- Model of an intermediate form
- Model of an intermediate form
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Crystal model made of cardboard
- Stereoscopic pictures of crystal grids from v. Laue and v. Mises
- Two rhombic dodecahedrons
- Rhombusthirtyflat with the symmetries of the icosahedron group
- Cube with joining surfaces of the balance point and the borders
- Cube with joining surfaces of the balance point and the borders
- Diapositiv: Struktur des Diamanten
- Slide: Icosahedron
- Slide: Rhombus dodecahedron
- Slide: Icosahedron
- Slide: Cube and rhombus dodecahedron
- Slide: Tetrakishexahedron and ocahedron
- Slide: Cube and octahedron
- Slide: Crystals
- Slide: Crystals
- Slide: Rhombus dodecahedron
- Slide: Dodecahedron
- Slide: Penetration of two cubes
- Slide: 2 regular tetrahedrons
- Slide: Penetration of octahedron and prism
- Slide: Penetration of two tetrahedrons

- III
- Isometry groups
- IV
- Polyhedrons
- V
- 4-dimensional regular configurations
- XX
- Others

- C
- Topology
- D
- Kinematics and Mechanics
- E
- Differential Geometry
- F
- Algebra
- G
- Analysis, Probability Theory
- H
- Theory of Functions of Complex Variables
- J
- Differential Equations, Wave Theory
- K
- Geometrical Optics
- L
- Instruments and Devices.
- M
- History of Mathematis and Astronomy
- Z
- Other

A regular body/polyhedron is a subset of the three dimensional space, which is limited by planes. The surface contains of straight plane fragments, lines and vertices. Crystals can be regarded as regular integer point systems. They are classified by their symmetries.