We give a short proof of a lower bound for the smallest singular value mentioned by Hong and Pan. One of our results improves their theorem. We obtain another lower bound that is sharp. An example shows that these results can be quite accurate.
Yi-Sheng, Y., & Dun-he, G. (1997). A note on a lower bound for the smallest singular value. Linear Algebra and Its Applications, 253(1–3), 25–38. https://doi.org/10.1016/0024-3795(95)00784-9