China Work Visa (Z)
The employer will send you a government issued Employment Permit and Visa
Notification Letter which you must submit with a photocopies with your
application. Family members accompanying an applicant may also apply for a
Z visa submitting a 'proof of relationship' instead i.e. their marriage
certificate for a spouse, or birth certificate for a child. http://www.travelchinaguide.com/embassy/visa/work.htm