Maintenance of NAS enroute stage A air traffic control system, change 1. 

 - [Washington, D.C.,  1969]. 
 - [286] p. :  ill. 
<br/><br/> Handbook.  [Oct. 16, 1969].  4to.  [Cancellation date July 1, 1970. Issued with perforations].  CRDP Program Historic Shelflist record. 
<br/><br/> Official use. Not available. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Air traffic control.
<br/><br/><label>GPO Item No.: </label>0431-C-02 
<br/><br/><label>Gov. Doc. Class. No.: </label>TD 4.8/2:6100.1/CH.1