Typescript import with Nodejs

I'm trying to create a simple node app to test out typescript, and I'm having trouble with the type definitions and import. Here is my code:

/// <reference path="./node.d.ts" />
/// <reference path="./underscore.d.ts" />

import _ = require('underscore');

I'm getting an error File node.d.ts not found. This stops TS from building. The d.ts files are in the same directory, but won't resolve. Can someone point me in the right direction?