Gaya APA

Chapman, O, L. (1947). Water Levels and Artesian Pressure in Observation Wells in The United States in 1947 Part. 6 . : United States Government Printing Office.

Gaya MLA

Chapman, Oscar, L. "Water Levels and Artesian Pressure in Observation Wells in The United States in 1947 Part. 6". : United States Government Printing Office, 1947. Text.