Note 9 - Convertible Notes - Convertible Notes (Details) - Convertible Debt [Member] - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Long-term Debt	$ 4,316,324	$ 3,670,172
Less current portion	2,388,806	1,461,979
Loans and convertible notes payable, less current portion	1,927,518	2,208,193
Convertible Payable 1 [Member]
Long-term Debt	838,919	880,567
Convertible Payable 2 [Member]
Long-term Debt	3,460,205	2,789,605
Convertible Payable 3 [Member]
Long-term Debt	$ 17,200

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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