Macmillan Encyclopedia of Physics
                                    
                                        
                                        SEP 01, 1997
                                    
                                
                            
                            
                            
                              DOI: 10.1063/1.881915
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More about the Authors
Brian Pippard. Cambridge University, Cambridge, UK.
                                © 1997. American Institute of Physics
                            
                            
                        