1. Radiation exposure levels within timber industries in Calabar, Nigeria;Inyang SO;J Med Phys,2009
2. Measurement of terrestrial gamma radiation dose and evaluation of annual effective dose in Shimoga District of Karnataka State, India;Rangaswamy DR;Radiation Prot Environ,2016
3. STUK (2010) The radioactivity of building materials and ash. Helsinke, Radiation and Nuclear Safety Authority
4. National Council on Radiation Protection and Measurements (1987) Exposure of the population of the United States and Canada from natural background radiation. National Council on Radiation Protection and Measurements Report no. 94. NCRP, Bethesda
5. Measurement of radioactivity in books and calculations of resultant eye doses to readers;Imtiaz MA;Health Phys,2005