APA (7th ed.) Citation

Plotkin, R., De la Ree, G., & Gaetz, R. R. (1940). Sun spots. Solar Press.

Chicago Style (17th ed.) Citation

Plotkin, Roy, Gerry De la Ree, and Roderick Ruskin Gaetz. Sun Spots. Westwood, N.J.: Solar Press, 1940.

MLA (9th ed.) Citation

Plotkin, Roy, et al. Sun Spots. Solar Press, 1940.