On some special iteration groups
Volume 83 / 1973
                    
                    
                        Fundamenta Mathematicae 83 (1973), 67-74                    
                                        
                        DOI: 10.4064/fm-83-1-67-74                    
                                    
                                                                
                             
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            