Aftonian sands and gravels in western Iowa

B. SHIMEK
1909 Geological Society of America Bulletin  
P re se n te d b y title befo re th e S o c ie ty D e c e m b e r 3 1 , 1 9 0 8 )
doi:10.1130/gsab-20-399 fatcat:lmcopnstkvgehaqh3e22ragvua