Physics Letters A
Physics Letters A > 2006 > 356 > 4-5 > 290-293
Physics Letters A > 2006 > 356 > 4-5 > 339-345
Physics Letters A > 2006 > 356 > 4-5 > 385-391
Physics Letters A > 2006 > 356 > 4-5 > 290-293
Physics Letters A > 2006 > 356 > 4-5 > 339-345
Physics Letters A > 2006 > 356 > 4-5 > 385-391