APA (7th ed.) Citation

Väisälä, Y., & Oterma, L. (1951). Formulae and directions for computing the orbits of minor planets and comets.

Chicago Style (17th ed.) Citation

Väisälä, Yrjö, and Liisi Oterma. Formulae and Directions for Computing the Orbits of Minor Planets and Comets. Turku, 1951.

MLA (9th ed.) Citation

Väisälä, Yrjö, and Liisi Oterma. Formulae and Directions for Computing the Orbits of Minor Planets and Comets. 1951.

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