A tridimensional intertwining inside a torus [Un entrelacs tridimensionnel à l'intérieur d'un tore].
PR[x,y,z] = = = PA[PX[x,y,z],PY[x,y,z],PZ[x,y,z]]
PA[x,y,z] = =
PX[x,y,z] =
PY[x,y,z] =
PZ[x,y,z] =