TY  - RPRT
TI  - Problems of Pleistocene Stratigraphy
AU  - L.L. Ray
PY  - 1949
DO  - 10.1130/0016-7606(1949)60[1463:pops]2.0.co;2
UR  - https://pubs.usgs.gov/publication/70206701
ID  - 70206701
ER  -