[1] Tiwell S C, Seamans J F, Hamilton et al, Opt Lett,1991, 16(8):584-586
[2] Pfistner C, Albers P, Weber H P, IEEE J Q E, 1990,26(5): 827-829
[3] Baer T M, Head D F, Sakmoto bI, CLEO, Washington, 1989,paper FJ5
[4] Shannon D C, Wallace R W.Opt Lett, 1991,16(5):318-320
[5] Oka M, CLEO, Baltimore USA, 1991, paper CME7
[6] Berger J,Welch D F,Streifer et al, Opt Lett,1988f 13(4):306-308