APA (7th ed.) Citation

Regularity... & John Lewis, [. a. (2012). Regularity estimates for nonlinear elliptic and parabolic problems. Springer.

Chicago Style (17th ed.) Citation

Regularity... and [et al.] John Lewis. Regularity Estimates for Nonlinear Elliptic and Parabolic Problems. Springer, 2012.

MLA (8th ed.) Citation

Regularity... and [et al.] John Lewis. Regularity Estimates for Nonlinear Elliptic and Parabolic Problems. Springer, 2012.