mm_tdiff_multivariate_general
                        Moment-Matching Approximation for General
                        Multivariate t-Differences
mm_tdiff_multivariate_independent
                        Moment-Matching Approximation for Multivariate
                        t-Differences (Independent)
mm_tdiff_univariate     Moment-Matching Approximation for Univariate
                        t-Differences
mvtdiff_distributions   Distribution Functions for Multivariate
                        Approximated t-Difference
tdiff_distributions     Distribution Functions for Approximated
                        t-Difference
validate_approximation
                        Validate Moment-Matching Approximation
