usage.md

@@ -4,7 +4,6 @@
   - ICON-Atmosphere (NWP) <-> ICON-Waves
   - ICON-Output
   - [HD Model](https://nat-esm-system.dkrz.de/Optional%20Components/HD%20Model.html)
-    - ICON-A (NWP) -> HD
   - [Parflow](https://parflow.org/)
   - [mHM](https://mhm-ufz.org/)
   - [CoCip](https://elib.dlr.de/68002/1/Schumann_CoCiP_TAC2_DLR_FB_2010_10_p_69_74.pdf) (Contrail Cirrus Prediction Tool)