Sir,
I am Indian Professor. I wish to visit china for research purpose. I have been invited by govt agencies in china for this purpose. I want to stay for 70 days after entry. I want to apply 2.5 months before for visa. Which type of visa I should apply for? I also wish to accompany my wife with me. She will stay for less than 30 days. Can we apply together? What documents are required for both of us. She is also a working women.