Showalter, R. E. (1979). Hilbert space methods for partial differential equations.
Čikaški stil citiranjaShowalter, R E. Hilbert Space Methods for Partial Differential Equations. Pitman Advanced Publishing Program, San Francisco, 1979.
MLA način citiranjaShowalter, R E. Hilbert Space Methods for Partial Differential Equations. 1979.
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