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The term reionization-limited HI cloud (RELHIC) has been coined for an intergalactic HI cloud with dark matter, but no stars: like a galaxy except for the lack of stars (making it a dark galaxy). The existence of low-mass dark matter halos has been suggested by cosmological simulations and galaxy formation simulations that are based upon the Lambda-CDM model. However, the count of observed low-mass galaxies is far short of that suggested by the models, a discrepancy termed the dwarf galaxy problem. A population of RELHICs would provide some explanation, thus constitute supporting evidence for Lambda-CDM, and candidate RELHICs (such as Cloud-9) are of interest. I believe the phrase reionization-limited refers to a mechanism theorized that could such a cloud's star formation: at the time of reionization, within a certain dark-matter-halo mass-range, feedback (including ionizing radiation) might be able to quench its star formation so quickly and completely that the halo remains virtually without stars, soon cooling until the gas is neutral.