diff --git a/poly2tri/poly2tri-tests.ts b/poly2tri/poly2tri-tests.ts
index 2a73275ff..2f062b3be 100644
--- a/poly2tri/poly2tri-tests.ts
+++ b/poly2tri/poly2tri-tests.ts
@@ -1,4 +1,4 @@
-/// <reference path="../../dist/poly2tri.d.ts" />
+/// <reference path="poly2tri.d.ts" />
 
 function initializeCDT(): poly2tri.SweepContext {
     var contour = [
diff --git a/poly2tri/poly2tri.d.ts b/poly2tri/poly2tri.d.ts
index 8e2ac48f5..9b9edebd2 100644
--- a/poly2tri/poly2tri.d.ts
+++ b/poly2tri/poly2tri.d.ts
@@ -49,13 +49,13 @@ declare module poly2tri {
 
         static mul(s: number, p: IPointLike): Point;
 
-        static cross(a: number, b: number);
+        static cross(a: number, b: number): number;
 
-        static cross(a: IPointLike, b: number);
+        static cross(a: IPointLike, b: number): number;
 
-        static cross(a: IPointLike, b: IPointLike);
+        static cross(a: IPointLike, b: IPointLike): number;
 
-        static cross(a: number, b: IPointLike);
+        static cross(a: number, b: IPointLike): number;
 
         static toStringBase(p: IPointLike): string;