N.T.B, N.R.C <br/><br/>
Transportation research record No.1404 
N.R.C, N.T.B 
 - Washington  National Academy Press  1993 
 - 100 p 
<br/><br/>
<br/><br/><label>ISBN: </label>0-309-05550-4 
<br/><br/><label>Dewey Class. No.: </label>388.049  / NAT