Note 6 - Loss Per Share - Reconciliation of the Components of Basic and Diluted Net Loss Per Share (Details) - USD ($)	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Net loss for the period	$ (1,910,325)	$ (1,435,684)	$ (6,690,191)	$ (6,206,814)
Weighted average shares outstanding, basic (in shares)	6,550,068	6,357,113	6,449,345	6,257,512
Net loss attributable to common stock, basic, loss per share (in dollars per share)	$ (0.29)	$ (0.23)	$ (1.04)	$ (0.99)
Weighted average shares outstanding, diluted (in shares)	6,550,068	6,357,113	6,449,345	6,257,512
Net loss attributable to common stock, diluted, loss per share (in dollars per share)	$ (0.29)	$ (0.23)	$ (1.04)	$ (0.99)