APA (7th ed.) Citation

Perkins, G. D. (1971). The principles of electrical science, in S.I. units. English Universities Press.

Chicago Style (17th ed.) Citation

Perkins, G. D. The Principles of Electrical Science, in S.I. Units. London: English Universities Press, 1971.

MLA (8th ed.) Citation

Perkins, G. D. The Principles of Electrical Science, in S.I. Units. English Universities Press, 1971.