Robuta

https://docs.lib.purdue.edu/icec/1239/ "Rotary Volumetric Machines with a Rotating Piston/Cylinder" by Z. Gnutek and S. Pietrowicz By Z. Gnutek and S. Pietrowicz, Published on 01/01/98 https://docs.lib.purdue.edu/icec/1161/ "Heat Exchange in the Working Chamber of a Multivane Compressor" by Z. Gnutek and E. Kalinowski By Z. Gnutek and E. Kalinowski, Published on 01/01/96