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In this paper we consider $\phi^{4}$ and Sin - Gordon
theory and also we construct the general form of the stability
equation. In order to discuss the stability we use factorization
method. Using the associated Jacobi differential equation, we obtain
the exactly bound states of the $\phi^{4}$ and Sine - Gordon theory.
According to the supersymmetry approach, these bound states are
represented by two pairs of first order differential operators.
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