Boswell P G H <br/><br/>
Middle silurian rocks of North Wales 
Boswell P G H 
 -  1949 
 - p.  cm. 
<br/><br/><label>Standard No.: </label>52374 
<br/><br/><label>Source: </label> Textual 
<br/><br/><label>Subjects--Topical Terms: </label><br/> Silurian<br/>Geology
<br/><br/><label>Dewey Class. No.: </label>H523.562, H9