APA (7th ed.) Citation

Plotino & Armstrong, A. H. (1967). Plotinus. William Heinemann [etc.].

Chicago Style (17th ed.) Citation

Plotino and Arthur Hilary Armstrong. Plotinus. London [etc.]: William Heinemann [etc.], 1967.

MLA (9th ed.) Citation

Plotino and Arthur Hilary Armstrong. Plotinus. William Heinemann [etc.], 1967.