Warnakulasooriya, W.M.S.; de Silva, D.A.M.; Yapa, P.I.(Research Centre for Social Sciences, Faculty of Social Sciences, University of Kelaniya, Sri Lanka, 2016)
Kaushalya, P.M.K.T.; Yapa, P.I.; Weeraratne, W.M.J.(Research Centre for Social Sciences, Faculty of Social Sciences, University of Kelaniya, Sri Lanka, 2016)