K. W. Porter R. G. Tysdal W. A. Cobban J. E. Fox R. H. Hammond D. J. Nichols W. J. Perry Jr. D. D. Rice D. R. Setterholm G. W. Shurr J. C. Haley D. E. Lane S.B. Anderson E. B. Campen T. S. Dyman 1995 application/pdf 10.3133/i2474A en West-east stratigraphic transect of Cretaceous rocks in the northern Rocky Mountains and Great Plains regions, southwestern Montana to southwestern Minnesota reports