Thakshanika bahuvarana prashnoththara sangrahaya idikirim thakshanaya, Motor yanthrika thakshanaya , Viduli saha electronika thakshanaya ( a.po.sa. (sa. pela) (u.pela) , karmika vidyalavala thakshana pathamala hadarana sisun sandaha) - Wijesinghe, W. M. Sampath (2011)