1. C. Keller, The Escher Wyss AK Closed-Cycle Gas Turbine: Its Actual Development and Future Prospects, Paper Presented at ASME Meeting, November 26, 1945.
2. Closed-Cycle Gas Turbines: Operating Experience and Future Potential;Frutschi,2005
3. The Nuclear Gas Turbine-Towards Realization After Half a Century of Evolution;McDonald,1995
4. The Theory and Performance of Axial Flow Fans;Keller,1937
5. Aerodynamic turbine with closed circuit;Ackert,1942