APA (7th ed.) Citation

WB, B., & PR, C. (1967). A single variable variational approximation for a perturbed schrodinger equation. Proceedings of the National Academy of Sciences of the United States of America, 57(5), 1206. https://doi.org/10.1073/pnas.57.5.1206

Chicago Style (17th ed.) Citation

WB, Brown, and Certain PR. "A Single Variable Variational Approximation for a Perturbed Schrodinger Equation." Proceedings of the National Academy of Sciences of the United States of America 57, no. 5 (1967): 1206. https://doi.org/10.1073/pnas.57.5.1206.

MLA (9th ed.) Citation

WB, Brown, and Certain PR. "A Single Variable Variational Approximation for a Perturbed Schrodinger Equation." Proceedings of the National Academy of Sciences of the United States of America, vol. 57, no. 5, 1967, p. 1206, https://doi.org/10.1073/pnas.57.5.1206.