e;cplanatory note 



The series embodies rrsults of investigations, usually of 

 restricted scope, inlenc.'ed to cid or direct management or 

 utilization proctices end as guides for administrative or 

 legislative action. It is issued in limited quantities for the 

 official use of Fcder::!, S^ate or cooperating arsncies and in 

 proces:ed form fc. y and to ovoid delay 7n publiccticr 



Washington, D.C. 

 January 17-5' 



