(1961). [Addition or Additions of Certain Lands to the Effigy Mounds National Monument in the State of Iowa]. U.S. G.P.O.].
Chicago Style (17th ed.) Citation[Addition or Additions of Certain Lands to the Effigy Mounds National Monument in the State of Iowa]. [Washington: U.S. G.P.O.], 1961.
MLA (9th ed.) Citation[Addition or Additions of Certain Lands to the Effigy Mounds National Monument in the State of Iowa]. U.S. G.P.O.], 1961.
Warning: These citations may not always be 100% accurate.