al-khafaji, Khlood A. A. “Determination of Heavy Metals Tolerance and Their Damaging Effects on a Local Soil Thermophilic Isolate Bacillus Stearothermophilus”. Journal of Biotechnology Research Center, vol. 10, no. 1, Jan. 2016, pp. 50-56, doi:10.24126/jobrc.2016.10.1.464.