Symmetric scheme for superdense coding between multiparties

Abstract
Recently Liu, Long, Tong, and Li [Phys. Rev. A 65, 022304 (2002)] proposed a scheme for superdense coding between multiparties. This scheme seems to be highly asymmetric in the sense that only one sender effectively exploits entanglement. We show that this scheme can be modified in order to allow more senders to benefit from the entanglement-enhanced information transmission.