NED object is B2 0844+31B; Reference is 1987A&AS...67..395J

   FIGURE 4.-(i) The distribution of the rotation of the polarization position
 angle of B0844+316 between 0.6 GHz and 1.4 GHz measured from the North towards
 the East. The two levels in the total intensity contour map at 0.6 GHz are 10
 and 80 mJy per beam.