Church, R. J. <br/><br/>
Linear program length & pupil performance :  an experimental study / 
R. J. Church. 
 - Wellington :  New Zealand Council for Educational Research,  1972. 
 - 68 p. :  ill. ;  22 cm. 
 - Educational Research series  no.49. .
<br/><br/><label>Subjects--Topical Terms: </label><br/>Programmed instruction