Editorial key: rust: German origin formations and advances; blue-green: lower/interior formations and subsidiary directional strokes; color does not establish allegiance; gray dashed line and dotted boundaries: source line distinctions, not newly inferred dates. Hatching and stipple distinguish source areas. U1 marks provisional fine symbols/unit numbers. No calibrated scale.
1986 geometry; later video/Richards schematic is substantially simpler. Open diagram.