Syrocki, B. John. <br/><br/>
What is a rock / 
B. John Syrocki. 
 - Chicago:  Benefic Press,  1961. 
 - 48 p. :  ill. ;  20 cm. 
 - The what is it series. .
<br/><br/>55  55 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Petrology
<br/><br/><label>Dewey Class. No.: </label>552 / S85w