One of his contributions in middle of 1970s together with colleges was independently clarify the relationship between topology (Homotopy) of order parameter manifold and defects. Together with few work about topological property of instanton in high energy physics during that time, those work are enter in textbook nowaday. In 1996, the Chiral anomaly originating from the Fermi/Weyl point in superfluid helium-3 has been observed. After almost twenty years, same phenomena has been observed in solid material experiment.