Hack, John Tilton  1913-1991 <br/><br/>
Studies of longitudinal stream profiles in Virginia and Maryland / 
by John T. Hack. 
 -- Washington :   United States Government Printing Office,   1957 
 - 97 p. + 1 map. -- 
 (Geological Survey Professional Paper  ;  294-B).
<br/><br/><label>Subjects--Topical Terms: </label><br/>Maryland<br/>Ríos<br/>Virginia
<br/><br/><label>Universal Decimal Class. No.: </label>556.53(752+755)