for (let i: number = index - 1; i >= 0; i--) {
            const entries: GraphicalStaffEntry[] = this.verticalGraphicalStaffEntryContainers[i].StaffEntries;
            for (let idx: number = 0, len: number = entries.length; idx < len; ++idx) {
                const entry: GraphicalStaffEntry = entries[idx];
                if (entry && entry.sourceStaffEntry.ParentStaff.ParentInstrument.Visible) {