APA (7th ed.) Citation

Kustaanheimo, P. E. (1959). On vector methods in spherical astronomy. Societas Scientiarum Fennica.

Chicago Style (17th ed.) Citation

Kustaanheimo, Paul Edwin. On Vector Methods in Spherical Astronomy. Helsinki: Societas Scientiarum Fennica, 1959.

MLA (9th ed.) Citation

Kustaanheimo, Paul Edwin. On Vector Methods in Spherical Astronomy. Societas Scientiarum Fennica, 1959.