Niels Bohr collected works 
/ North-Holland Publishing Company 
 - Amsterdam:   North Holland Publishing Company,  
<br/><br/> Vol. 1 Early works(1905-1911)<br/>Vol. 3 The correspondence principle(1918-1923)<br/>Vol. 4 The periodic system (1920-1923)<br/>Vol. 5 The emergence of quantum mechanics (Mainly 1924-1926)<br/>Vol. 6 Foundations of quantum physics I (1926-1932)<br/>Vol. 9 Nuclear physics (1929-1952) 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Science
<br/><br/><label>Subjects--Index Terms: </label>Physics 
<br/><br/><label>Universal Decimal Class. No.: </label>539.1(081) BOHR  / L2.9