APA (7th ed.) Citation

Gomes, D., & Oliveira, E. C. D. The second-order Klein-Gordon field equation. Wiley.

Chicago Style (17th ed.) Citation

Gomes, D., and E. Capelas De Oliveira. The Second-order Klein-Gordon Field Equation. Wiley.

MLA (9th ed.) Citation

Gomes, D., and E. Capelas De Oliveira. The Second-order Klein-Gordon Field Equation. Wiley.

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