1. Analysis of the concentrations of natural radionuclides in rivers in Kota Tinggi District, Malaysia;Abdul Rahman;J. Nucl. Relat. Technol.,2004
2. Airborne Magnetometer and Scintillation Counter Survey of Kedah, Perak, Selangor, Terengganu, Pahang, dan Johor;Agoes,1958
3. Basic Linear Geostatistics;Amstrong,1998
4. Radiological Study in Perak State and its Radiological Health Impact;Apriantoro,2008
5. Natural background dose measurements in South Cameroon;Ateba;Radiat. Prot. Dosim.,2010