Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Aug. 31, 2020	Nov. 30, 2019
Allowance for doubtful accounts	$ 42,542	$ 22,925
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	500,000	500,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	9,500,000	9,500,000
Common stock, issued (in shares)	4,465,004	4,321,087
Treasury stock (in shares)	33,313	18,842

Amount of allowance for credit loss on accounts receivable, classified as current.

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