A feed of cases that cite 252 U.S. 399.
http://supreme.justia.com/
252 U.S. 3992007-12-13
http://supreme.justia.com/us/235/537/index.html
South Covington & Cincinnati Ry. Co. v. Covington, 235 U.S. 537 (1915)1915-1-1
http://supreme.justia.com/us/179/388/index.html
Chesapeake & Ohio Ry. Co. v. Kentucky, 179 U.S. 388 (1900)1900-1-1
http://supreme.justia.com/us/252/408/index.html
Cincinnati, Covington & Erlanger Ry. Co. v. Kentucky, 252 U.S. 408 (1920)1920-1-1