Watson, R. A. <br/><br/>
The use of computer system accounting data to measure the effect of a system modification / 
R. A. Watson. 
 - California :  Rand Corporation,  1970. 
 - 15 p. ;  28 cm. 
 - The Rand paper series ;  p.4536-1 .
 - Rand paper series ;  p.4536-1 .
<br/><br/>Includes bibliographical references.