On the category of commutative connected graded Hopf algebras over a perfect field
Volume 101 / 1978
                    
                    
                        Fundamenta Mathematicae 101 (1978), 137-149                    
                                        
                        DOI: 10.4064/fm-101-2-137-149                    
                                    
                                                                
                             
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            