CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts	$ 1,489,171	$ 1,253,571
Ordinary shares, par value	$ 0.01	$ 0.01
Ordinary shares, shares authorized	100,000,000	100,000,000
Ordinary shares, shares issued	20,000,000	20,000,000
Ordinary shares, shares outstanding	19,791,110	19,791,110
Treasury stock, shares	208,890	208,890

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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