required documents for visa to ITM

Dear Sir,

I am Maamoun Elwani original from Syria , but i leave in Turkey from almost one year and i have my residence in Turkey

I want to go to China with my son he is 20 years old, to visit ITM fair in October 2016 , already i have my won co.LTD in Turkey .

Please confirm to me the necessary document i have to bring with me to get the entry permit, and already i have with my son an certified invitation from one Chinese company

Thank you
B.R.
Elwani