Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	May 31, 2018	Nov. 30, 2017
Allowance for doubtful accounts	$ 22,829	$ 32,298
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)	4,208,233	4,158,752
Treasury stock (in shares)	9,286	1,954

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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