Note 5 - Intangible Assets (Details Textual) - USD ($)
12 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Finite-Lived Intangible Assets, Remaining Amortization Period (Year) 6 years  
Amortization of Intangible Assets $ 2,880 $ 2,882
Minimum [Member]    
Finite-Lived Intangible Asset, Useful Life (Year) 10 years  
Maximum [Member]    
Finite-Lived Intangible Asset, Useful Life (Year) 15 years