Galaxy model adopted from an N-body simulation snapshot: left: gas surface density projected on the sky with an inclination of 26° and PA = 15°, and right: corresponding gas isovelocity curves separated by 24.3 km s⁻¹ and ranging from −109.4 km s⁻¹ to +109.4 km s⁻¹. The locations of NE image (A), SW image (B), and a third central image (C) close to the lensing-galaxy center are indicated together with the schematic contours of the Einstein ring, which are conspicuous at cm wavelengths.