\left\{\begin{array}{c} \begin{array}{l} \left(A_{1} \land A_{2} \land \ldots \land A_{l}\land B_{1} \land B_{2} \land \ldots \land B_{m}\land C_{1} \land C_{2} \land \ldots \land C_{n}\right) = \\ \left(A_{1} \land A_{2} \land \ldots \land A_{l} \land \left(B_{1} \land B_{2} \land \ldots \land B_{m}\right)\land C_{1} \land C_{2} \land \ldots \land C_{n}\right) \end{array} \end{array} \textrm{ if } \left(A_{1} \in \mathbb{B}\right) , \left(A_{2} \in \mathbb{B}\right) , \ldots , \left(A_{l} \in \mathbb{B}\right), \left(B_{1} \in \mathbb{B}\right) , \left(B_{2} \in \mathbb{B}\right) , \ldots , \left(B_{m} \in \mathbb{B}\right), \left(C_{1} \in \mathbb{B}\right) , \left(C_{2} \in \mathbb{B}\right) , \ldots , \left(C_{n} \in \mathbb{B}\right)\right..