1. The radiation field in air due to distributed gamma-ray sources in the ground;Beck,1968
2. The physics of environmental radiation fields;Beck,1974
3. Temporal variations of the natural radiation field;Beck,1981
4. High pressure argon ionization chamber system for the measurement of environmental radiation exposure rates;de Campo,1972
5. TLD measurements and model calculations of environmental radiation exposure ra tes;de Planque,1980