Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Aug. 31, 2019	Nov. 30, 2018
Allowance for doubtful accounts	$ 24,654	$ 25,100
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)	4,316,087	4,225,050
Treasury stock (in shares)	17,875	9,286

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

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