Homeotopy groups of orientable 2-manifolds
Tom 77 / 1972
                    
                    
                        Fundamenta Mathematicae 77 (1972), 115-124                    
                                        
                        DOI: 10.4064/fm-77-2-115-124                    
                                    
                                                                
                             
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            