How to block a country ip address on cisco router 1760

At my company, i don’t want any ip address from China to access to my server using CISCO routeur 1760. After doing some research on the net, I knew there are lot of ip addresses in China. I try to use ACLs, but it’s quite complicated to block ip addresses from china as there are a lot. Please help me.

Thanks in advance.
Frati David.