Quarterly report pursuant to Section 13 or 15(d)

Accounts receivable, net (Details)

v3.7.0.1
Accounts receivable, net (Details) - USD ($)
Jun. 30, 2017
Dec. 31, 2016
Accounts receivable $ 45,925,897 $ 49,460,347
Less: allowance for doubtful accounts 3,188,690 3,179,578
Accounts receivable, net $ 42,737,207 $ 46,280,769