Note 7 - Convertible Notes - Convertible Notes (Details) - Convertible Debt [Member] - USD ($)	Jun. 30, 2021	Dec. 31, 2020
Long-term Debt, gross	$ 2,158,638	$ 6,730,448
Less unamortized debt discount	19,248	0
Long-term Debt, Total	2,139,390	6,730,448
Less current portion	2,115,390	6,652,448
Convertible notes payable, less current portion	24,000	78,000
Convertible Notes 1[Member]
Long-term Debt, gross	891,282	867,641
Convertible Notes 2 [Member]
Long-term Debt, gross	1,236,794	5,862,807
Convertible Notes 3 [Member]
Long-term Debt, gross	$ 30,562	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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