MacKenzie, K. (1969). Scyphidia (Gerda) adunconucleata n. sp. and Trichodina borealis (Dogiel, 1940) Shulman et Shulman-Albova, 1953 (Protozoa Ciliata) from Young Plaice in Scottish Waters. Journal of Fish Biology. 1(3): 239-247.
Scyphidia (Gerda) adunconucleata n. sp. and Trichodina borealis (Dogiel, 1940) Shulman et Shulman-Albova, 1953 (Protozoa Ciliata) from Young Plaice in Scottish Waters