Potgieter, Jenni-Marí; Swanepoel, De Wet; Heinze, Barbara M.; Hofmeyr, Louis Murray; Burger, André A.S.; Hamersma, Herman(Cambridge University Press, 2014-04)
Tao, Karina F.M.; Brennan-Jones, Christopher G.; Capobianco-Fava, Dirce M.; Jayakody, Dona M.P.; Friedland, Peter L.; Swanepoel, De Wet; Eikelboom, Robert H.(American Speech-Language-Hearing Association, 2018-07-13)