diff --git a/h24s_25/src/ts/higherorderfunctionball.ts b/h24s_25/src/ts/higherorderfunctionball.ts
index fb44096..833c089 100644
--- a/h24s_25/src/ts/higherorderfunctionball.ts
+++ b/h24s_25/src/ts/higherorderfunctionball.ts
@@ -1,5 +1,5 @@
 import{BallTypeEnum} from './balltypes';
-import {BallInterface, HigherOrderFunctionBallInterface, NumberBallInterface, FunctionBallInterface} from './ballInterface';
+import {BallInterface, HigherOrderFunctionBallInterface, FunctionBallInterface} from './ballInterface';
 
 export class HigherOrderFunctionBall<
     S1 extends BallInterface|null,