1. Environmental radioactivity at Risoe April 1, 1957-March 31, 1958;Aarkrog;Risoe Rep.,1958
2. Environmental radioactivity at Risoe April 1, 1958-March 31, 1959;Aarkrog;Risoe Rep.,1959
3. Environmental radioactivity at Risoe in 1959;Aarkrog;Risoe Rep.,1960
4. Environmental radioactivity in Denmark in 1960;Aarkrog;Risoe Rep.,1961
5. Environmental radioactivity in Denmark in 1963;Aarkrog;Risoe Rep.,1964