We establish an upper bound of the measure of any level set of a stationary solution \documentclass[12pt]{minimal}
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$u$\end{document} of theGinzburg-Landau equation \documentclass[12pt]{minimal}
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\[ - \Delta u + \vert u \vert^2 u - au = 0 \] \end{document} subject to periodic boundary conditions. The obtained bound depends polynomially on the parameter \documentclass[12pt]{minimal}
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$a$\end{document}.