Endrika:Tsiahy:cy:GPC
R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), chapter Tsiahy:cy:GPC, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies
R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), chapter Tsiahy:cy:GPC, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies