Graphical methods in research /
Levens, A. S.
Graphical methods in research / [by] A.S. Levens. - New York : Wiley, c1965. - vi, 217 p. : ill.
Graphic methods--Research.
Statistics--Graphic methods.
Graphical methods in research / [by] A.S. Levens. - New York : Wiley, c1965. - vi, 217 p. : ill.
Graphic methods--Research.
Statistics--Graphic methods.