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If  $\{\mathscr A_t\}_{t\in\Omega}$ and $\{\mathscr B_t\}_{t\in\Omega}$ are  weakly*-measurable families of bounded Hilbert space operators such that  transformers $ X\mapsto \int_{\Omega}\mathscr A_t^* X \mathscr A_t d\mu(t)$ and $ X\mapsto \int_{\Omega}\mathscr B_t^* X \mathscr B_t d\mu(t)$ on $\mathcal B(\mathcal{H})$ have their spectra contained in the unit disc, then for all bounded operators $X$ \begin{equation} \bigl\vert\!\!\;\bigl\vert \Delta_{\mathscr A} X \Delta_{\mathscr B} \bigr\vert\!\!\; \bigr\vert \leqslant \biggl\vert \!\!\; \biggr\vert \, X -\! \int_{\Omega}\mathscr A_t^* X \mathscr B_t d\mu(t) \biggr\vert \!\!\; \biggr\vert , \label{zvezda} \end{equation} where $\Delta_{\mathscr A} \stackrel{def}{=} {s\!-\!\lim_{r\nearrow 1} \Bigl( I + \sum_{n=1}^{\infty}r^{2n}\!\! \int_{\Omega} \cdots \int_{\Omega} \bigl\vert \mathscr A_{t_1} \cdots \mathscr A_{t_n} \bigr\vert^2 d\mu^n(t_1,\!\cdots\!,t_n) \:\!\! \Bigr)^{-1/2}}$  and $\Delta_{\mathscr B}$ by analogy. If additionally $\sum_{n=1}^\infty\int_{{\Omega}^n} \bigl\vert \mathscr A_{t_1}^*\cdots\mathscr A_{t_n}^* \bigr\vert^2 d\mu^n(t_1,\!\cdots\!,t_n)$ and $\sum_{n=1}^\infty\int_{{\Omega}^n} \bigl\vert \mathscr B_{t_1}^*\cdots\mathscr B_{t_n}^* \bigr\vert^2 d\mu^n(t_1,\!\cdots\!,t_n)$ both represent bounded operators, then for all  $p,q,s\geqslant 1$  such that $\frac 1{q}+\frac1{s}=\frac 2{p} $ and for all Schatten $p$ trace class operators $X $ \begin{equation} \left\vert \!\!\; \left\vert \Delta_{\mathscr A}^{1-\frac1{q}}X \Delta_{\mathscr B}^{1-\frac1{s}} \right\vert \!\!\; \right\vert_p \leqslant \biggl\vert \!\!\; \biggl\vert \:\! \Delta_{\mathscr A^*}^{-\frac1{q}}\biggl( X-\!\int_{\Omega}\mathscr A_t^* X \mathscr B_t d\mu(t)\:\!\! \biggr)\,\Delta_{\mathscr B^*}^{-\frac1{s}} \:\! \biggr\vert \!\!\; \biggr\vert_p. \label{hag2} \end{equation} If at least one of those families consists of bounded commuting normal operators, then (\ref{zvezda}) holds for all unitarily invariant Q-norms. Applications to the shift operators are also given.

Norm inequalities for elementary operators and other inner product type integral transformers with the spectra contained in the unit disc