On M-hyponormal operators
Volume 65 / 1979
                    
                    
                        Studia Mathematica 65 (1979), 1-5                    
                                        
                        DOI: 10.4064/sm-65-1-1-5                    
                                    
                                                                
                             
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            