APA (7th ed.) Citation

Niskanen, E. (1945). Gravity formulas derived by the aid of the level land stations.

Chicago Style (17th ed.) Citation

Niskanen, E. Gravity Formulas Derived by the Aid of the Level Land Stations. Helsinki, 1945.

MLA (9th ed.) Citation

Niskanen, E. Gravity Formulas Derived by the Aid of the Level Land Stations. 1945.

Warning: These citations may not always be 100% accurate.