We introduce a useful and rather simple classes of BKP tau functions which which we shall shall call easy tau functions. We consider the large BKP hiearchy related to $O(2infty +1)$ which was introduced in cite{KvdLbispec} (which is closely related to the DKP $O(2infty) $hierarchy introduced in cite{JM}). Actually easy tau functions of the small BKP was already considered in cite{HLO}, here we are more interested in the large BKP and also the mixed small-large BKP tau functions cite{KvdLbispec}. Tau functions under consideration are equal to sums over partitions and to multi-integrals. In this way they may be appliciable in models of random partitions and models of random matrices. Here in the part II we consider multi-intergals and series of $N$-ply integrals in $N$. Relations to matrix models is explained. This paper may be viewed as a developement of the the paper by J.van de Leur cite{L1} related to orthogonal and symplectic ensembles of random matrices.
تحميل البحث