Beardall, J. & Entwisle, L. (1984). Internal pH of the obligate acidophile Cyanidium caldarium Geitler (Rhodophyta?). Phycologia 23: 297-399
Ford, T.W. (1984). A comparative ultrastructural study of Cyanidium caldarium and the unicellular red alga Rhodosorus marinus. Annals of Botany 53: 285-294.
Muravenko, O.V., Selyakh, I.O., Kononenko, N.V. & Stadnichuk, I.N. (2001). Chromosome numbers and nuclear DNA contents in the red microalgae Cyanidium caldarium and three Galdeiria species. European Journal of Phycology 36: 227-232.
Yoon, H.S., Muller, K.M., Sheath, R.G., Ott, F.D. & Bhattacharya, D. (2006). Defining the major lineages of red algae (Rhodophyta). Journal of Phycology 42: 482-492.