Position–velocity plot of the H i emission disk (black) compared to the tilted ring model, smoothed at the resolution of the observations (grey contours). The contour levels range between 1.7 mJy beam^-1 and 7 mJy beam^-1, with steps of 1.4 mJy beam^-1. The model describes a regularly rotating disk, with a warp in the inner part, oriented along the N-S axis. The two absorption features are shown in blue and red, at the resolutions of 11′′ and 30′′. Contour levels are −2, −8 mJy beam^-1 and −1.7, −3.5 mJy beam^-1, respectively.