00389nam a22001097a 4500008004100000040005500041100001600096245008800112260005800200300001000258650001100268230731b        |||||||| |||| 00| 0 eng d  aNational Science LibrarycNational Science Library  aKent, Allen  aCost-benefit model of some critical library operations in terms of use of materials  aWashington: bDivision of Science Information, c1978  a243p.  aReport