“…RE and the k’-th AE) happening together. Note that with these six parameters ( π i = 1,1 , π i = 1, k ′ , π i = 1,1 k ′ , π i = 2,1, π i = 2, k ′ , π i = 2,1 k ′ ) the SSR of the RE and the CE can be determined[7,16] and thus it can become apparent whether it is worth the combination of the RE with the AE in a CE. Usually π i 1 , π ik , are known, but π i ,1 k ′ is sometimes unknown[17].…”