00311nam a22001097a 4500082002000000100001800020245005700038260004900095300001200144526003700156650000800193  a551.307bNATcD  aN.A.S - N.R.C  aHighway research board bulletin 216 /cN.R.C - N.A.S  aWashington :bHighway Research Board,c1959.  a43 p. :  a0b0c0d551_307000000000000_NAT  aMCE