Consolidated Balance Sheets (Parentheticals) - USD ($)	Nov. 30, 2020	Nov. 30, 2019
Allowance for doubtful accounts	$ 51,175	$ 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
Preferred stock, outstanding (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)	4,470,004	4,321,087
Treasury stock (in shares)	35,097	18,842