APA (7th ed.) Citation

Alster, B. (1970). (Note on some unobserved duplicates).

Chicago Style (17th ed.) Citation

Alster, Bendt. (Note on Some Unobserved Duplicates). 1970.

MLA (8th ed.) Citation

Alster, Bendt. (Note on Some Unobserved Duplicates). 1970.

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