CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($)	Jun. 30, 2018	Jun. 30, 2017
Allowance for doubtful accounts on trade receivables (in dollars)	$ 13,389	$ 13,733
Common stock, par value (in dollars per share)	$ 1	$ 1
Prior Cumulative Preferred Stock, $5 Par Value: | Series A
Preferred stock, par value (in dollars per share)	$ 5	$ 5
Preferred stock, liquidation preference (in dollars)	$ 2,310,000	$ 2,280,000
Prior Cumulative Preferred Stock, $5 Par Value: | Series B
Preferred stock, par value (in dollars per share)	$ 5	$ 5
Preferred stock, liquidation preference (in dollars)	$ 2,265,000	$ 2,235,000
Cumulative Preferred Stock, $20 Par Value: | Series A
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, liquidation preference (in dollars)	$ 5,194,796	$ 5,136,263
Cumulative Preferred Stock, $20 Par Value: | Series B
Preferred stock, par value (in dollars per share)	$ 20	$ 20
Preferred stock, liquidation preference (in dollars)	$ 846,594	$ 837,055