Assessment of occupational exposure due to external sources of radiation :  safety guide  / 
jointly sponsored by the International Atomic Energy Agency and the International Labour Law 
 - Vienna :  International Atomic Energy Agency,  1999 
 - 89 p, :  ill. ;  24 cm. 
 - Safety standards series ;  no. RS-G-1.3 .
<br/><br/>Refrences: p. 47-49 
<br/><br/><label>ISBN: </label>9201017995