Marshall, R. B.  1867-1949. <br/><br/>
Results of spirit leveling in Iowa 1896 to 1909, inclusive. / 
R.B. Marshall chief geographer.  Work done in cooperation with the state of Iowa from 1907 to 1909, inclusive. 
 - Washington,  Govt. Print. Off.,  1911. 
 - 32 p.  pl. ;  24 cm. 
 - U.S. Geological survey. Bulletin 460 .
 - United States.  Geological Survey.  Bulletin ;  460. .
<br/><br/> Issued also as House doc. no. 1433, 61st Cong., 3d sess.  Includes index. 
<br/><br/><label>LCCN: </label>gs 11000328  
<br/><br/><label>Subjects--Geographic Terms: </label><br/>Iowa--Altitudes.
<br/><br/><label>LC Class. No.: </label>QE75  / .B9 no. 460