Fong, Albert. <br/><br/>
The air permeability of a commercial concrete pipe. 

 - Cambridge, MA :  MIT, Dept. of Civil Engineering,  1973. 
<br/><br/>Includes bibliographical references. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Heat exchangers.<br/>Air heaters.<br/>Pipe, Concrete.