Sewell, M. J. (1987). Maximum and minimum principles: A unified approach, with applications. Cambridge: Cambridge University Press.
Παραπομπή Chicago StyleSewell, M. J. Maximum and Minimum Principles: A Unified Approach, With Applications. Cambridge: Cambridge University Press, 1987.
Παραπομπή MLASewell, M. J. Maximum and Minimum Principles: A Unified Approach, With Applications. Cambridge: Cambridge University Press, 1987.
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