Hey guys, my mother in law was born in mainland china and moved permanently to Hong Kong in 1954, so she has a permanent Hong Kong ID and Hong Kong passport. We just received a notice that CIC is asking for Hukou report. How do I find an official document saying that Hukou is only used in mainland china and not part of Honk Kong system. I understand I can write a letter to explain this but I wanted to find an official letter saying that Hukou is not a system that is used on Hong Kong. thanks in advance.