ALARA : principles, practice and consequences : proceedings of the symposium on \'ALARA\'-quantitative optimization techniques for radiation protection in the nuclear industry, held by The Institution of Nuclear Engineers, London, 18 September 1986 - SYMPOSIUM ON \'ALARA\'-QUANTITATIVE OPTIMIZATIONS TECHNIQUES FOR RADIATION PROTECTION IN THE NUCLEAR INDUSTRY (1986 : London) (Adam Hilger, 1987)