Gregory, J. W. <br/><br/>
General stratigraphy. 

 - London :  Methuen,  1931. 
 - 285 p. :  il. ;  19 cm 
 - Methuen's Geological Series .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Estratigrafía
<br/><br/><label>Index Terms--Genre/Form: </label><br/>Libro
<br/><br/><label>Universal Decimal Class. No.: </label>551.7