Van Der Werf, P.P. <br/><br/>
An H I study of HII regions and dark clouds 
P.P. Van Der Werf                                          
 - Groningen  Rijksuniversiteit Te Groningen  1961 
 - xiv, 209p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Astronomy and Astrophysics thesaurus<br/>Dark clouds<br/>H II regions
<br/><br/><label>Universal Decimal Class. No.: </label>043:52  / WER