The sky field around the position of B0528+134, as in Fig. 2. The map of CO emission at lower left superposes the integrated intensity at 0 − 4 km s^-1 as blue contours against a background grayscale representing emission at v = 8 − 12 km s^-1. Very strong CO lines are seen in the foreground gas as shown in the upper right panel: positions at which they originate are indicated at lower left.