Gossez, J. P., Gossez, J. P., Lami Dozo, E. J., Mawhin, J., & Waelbroeck, L. (1976). Nonlinear operators and the calculus of variations: Summer school held in Bruxelles, 8-19 September, 1975. Berlin: Springer-Verlag.

Gossez, J. P., J. P. Gossez, E. J. Lami Dozo, J. Mawhin, and L. Waelbroeck. Nonlinear Operators and the Calculus of Variations: Summer School Held in Bruxelles, 8-19 September, 1975. Berlin: Springer-Verlag, 1976.

Gossez, J. P., et al. Nonlinear Operators and the Calculus of Variations: Summer School Held in Bruxelles, 8-19 September, 1975. Berlin: Springer-Verlag, 1976.