Currently, forty-two thallium, forty-two lead, forty-one bismuth, and forty-two polonium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
@article{arxiv.1201.4474,
title = {Discovery of the thallium, lead, bismuth, and polonium isotopes},
author = {C. Fry and M. Thoennessen},
journal= {arXiv preprint arXiv:1201.4474},
year = {2015}
}