Freedman, Paul. <br/><br/>
The principles of scientific research / 

 - Washington,  Public Affairs Press  1950 
 - 222 p.  diagrs.  23 cm. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Research.
<br/><br/><label>Dewey Class. No.: </label>813.33  / FRP 1950