Change 1 to standards for airport sign systems. 

 - [Washington, D.C.,  1991]. 
 - v. 
<br/><br/> Nov. 13, 1991.  Shipping list no. : 92-0073-P.  CRDP Program Historic Shelflist record. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Airports--Marking--Standards--United States.
<br/><br/><label>GPO Item No.: </label>0431-A-27 
<br/><br/><label>Gov. Doc. Class. No.: </label>TD 4.8/5:150/5340-18 C/CH.1