The presence of radioactive materials in soil, sand and sediment samples of Potenga sea beach area, Chittagong, Bangladesh: Geological characteristics and environmental implication by Yasmin, Sabina, Barua, Bijoy Sonker, Khandaker, Mayeen Uddin, Kamal, Masud, Abdur Rashid, Md., Abdul Sani, Siti Fairus, Ahmed, Hossain, Nikouravan, Bijan, Bradley, David Andrew