The angular parts of matrix elements are calculated for the computationally most complicated exchange terms of the spin-other-orbit interaction for pf and p⁵f configurations. The matrix elements in these configurations are represented by three exchange radial Marvin integrals. A thorough analysis of expressions for calculation of the matrix elements is performed in the LSJM representation and the representation of uncoupled angular momenta in connection with permutation of electrons (the passage from the pf and p⁵f configurations to pf and f¹³p configurations).