Indian standard dimensions for circular - head steel cowl ventilators; IS : 3273 - 1966 

 - New Delhi  Indian Standard Institution  1966 
 - 5 p. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Indian Standard
<br/><br/><label>Dewey Class. No.: </label>621.61  / I81