Note 3 - Summary of Significant Accounting Policies - Fair Value of Level 3 Instruments (Details) - Derivative Financial Instruments, Liabilities [Member] |
6 Months Ended |
---|---|
Jun. 30, 2019
USD ($)
| |
Balance at beginning of year | |
Warrants issued in connection with public offering (See Note 8) | 376,497 |
Change in fair value of derivative liability | 5,750 |
Balance at end of period | $ 370,747 |