(4) Balje, O. E., A Study on Design Criteria and Matching of Turbo-machines (Part B), Trans. ASME Ser. A. 84-1 (1962-1), 103
(5) Rodgers, C., Specific Speed and Efficiency of Centrifugal Impellers, ASME Publication “Performance Prediction of Centrifugal Pumps and Compressors”,(1980-3), 191