Kansas Geological Survey, Current Research in Earth Sciences, Bulletin 243, part 1
Sedimentology and Ichnology of Paleozoic Estuarine and Shoreface Reservoirs, Morrow Sandstone, Lower Pennsylvanian of Southwest Kansas, USA

Fig. 40. Facies J. Planar crossbedded, medium- to fine-grained sandstone with vertical Ophiomorpha irregulaire (Kendrick).