Stephen, Alexander charles <br/><br/>
The phyla sipuncula and Echiura 

 - London  British Museum  1972 
 - vii,528p.  26cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Sipunculida
<br/><br/><label>LC Class. No.: </label>QL391.S5S73