Kinematical information over the entire disk of a spiral galaxy can be used in a new way to locate the position of the corotation resonance. The spiral residual velocity field has a global appearance that is distinctly different inside and outside the corotation resonance radius. Inside the corotation radius, the spiral velocity field shows a single spiral feature (that is, a single approaching-receding "spiral arm" pair). Outside the corotation radius, there are three spiral features (approaching-receding arm pairs). The corotation radius is located where this morphological change occurs. The effect is a consequence of geometric phase. It should apply generally, regardless of the functional form of the velocity perturbation due to a spiral arm, if the spiral structure is wave-based.
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B. Canzian (1993) studied this question.