Spear, Mary Eleanor. <br/><br/>
Practical charting techniques / 
Mary E. Spear. 
 - New York :  McGraw-Hill,  1969 
 - xxii, 394 p. :  illus. ;  23 cm. 
<br/><br/>Bibliography: p. 369-371. 
<br/><br/> Open access. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Statistics--Graphic methods.