Use function from one JScript WebResource in another

I added a new custom button to the ribbon and clicking of that button calls javascript function from JScript WebResource. But in that function  I would like to call another function from another JScript WebResource. For example I want to use CrmRestKit.ByQueryAll function from CrmRestKit library, but when I try it error "CrmRestKit is undefined" displayed. What can I do? I added CrmRestKit.js to webresources in my solution.