Effectivess of reading and mathematics software products  findings from two student cohorts.  [electronic resource] : 

 - Washington, DC :  U. S. Department of Education, Institute of Education Sciences, National Center for Education Evaluation and Regional Assistance,  2009. 
 - 1 v. :  digital, PDF file 
<br/><br/> "NCEE 2009-4041."  "February 2009."  CRDP Program Historic Shelflist record. 
<br/><br/><label>GPO Item No.: </label>0455-R (online) 
<br/><br/><label>Gov. Doc. Class. No.: </label>ED 1.602:SO 2