10. Other Current Liabilities (Details Narrative) - USD ($)	Feb. 28, 2019	May 31, 2018
Accrued dividends	$ 98,170	$ 179,218
Series D-2017 Preferred Stock [Member]
Accrued dividends	$ 98,170	164,237
Series C-2016 Preferred Stock [Member]
Accrued dividends		$ 14,981

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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