APA (7th ed.) Citation

John, F. (1977). Restrictions on the coefficients of hyperbolic systems of partial differential equations. Proceedings of the National Academy of Sciences - PNAS, 74(10), 4150. https://doi.org/10.1073/pnas.74.10.4150

Chicago Style (17th ed.) Citation

John, F. "Restrictions on the Coefficients of Hyperbolic Systems of Partial Differential Equations." Proceedings of the National Academy of Sciences - PNAS 74, no. 10 (1977): 4150. https://doi.org/10.1073/pnas.74.10.4150.

MLA (9th ed.) Citation

John, F. "Restrictions on the Coefficients of Hyperbolic Systems of Partial Differential Equations." Proceedings of the National Academy of Sciences - PNAS, vol. 74, no. 10, 1977, p. 4150, https://doi.org/10.1073/pnas.74.10.4150.