Organelle origins: Energy-producing symbionts in early eukaryotes? Mitchell L Sogin  Current Biology  Volume 7, Issue 5, Pages R315-R317 (May 1997) DOI: 10.1016/S0960-9822(06)00147-3

Figure 1 A hydrogenosome of Trichomonas foetus, a close relative of the protist T. vaginalis discussed in the text, showing the characteristic marginal plate (m) and dense core (c). (Photograph courtesy M. Müller and H. Shio, reproduced with permission from [11].) Current Biology 1997 7, R315-R317DOI: (10.1016/S0960-9822(06)00147-3)