@ARTICLE{investigation2014,
     Title={Investigation on polarization dependent bidirectional hybrid (WDM/TDM) utilizing QAM modulation with different amplifiers},
     Author={Rakesh Goyal, R. S. Kaler},
     Journal={Optoelectronics And Advanced Materials-Rapid Communications},
     Volume={8},
     Number={0},
     Pages={631-634},
     Publisher={},
     Year={2014}
}