APA (7th ed.) Citation

Appell, J., De Pascale, E., & Vignoli, A. (2004). Nonlinear spectral theory. De Gruyter. https://doi.org/10.1515/9783110199260

Chicago Style (17th ed.) Citation

Appell, Jürgen, Espedito De Pascale, and Alfonso Vignoli. Nonlinear Spectral Theory. Berlin [u.a.]: De Gruyter, 2004. https://doi.org/10.1515/9783110199260.

MLA (9th ed.) Citation

Appell, Jürgen, et al. Nonlinear Spectral Theory. De Gruyter, 2004. https://doi.org/10.1515/9783110199260.