On sums of two kth powers: an asymptotic formula for the mean square of the error term
Volume 92 / 2000
                    
                    
                        Acta Arithmetica 92 (2000), 263-276                    
                                        
                        DOI: 10.4064/aa-92-3-263-276                    
                                    
                                                                
                             
             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                             
                                                         
                                                            