Practical research :
Leedy, Paul D.
Practical research : planning and design / Paul D. Leedy, Jeanne Ellis Ormrod. - 9th ed. - Boston : Pearson, 2010. - xvii, 336 p.
0131365667 :
Research--Methodology.
Practical research : planning and design / Paul D. Leedy, Jeanne Ellis Ormrod. - 9th ed. - Boston : Pearson, 2010. - xvii, 336 p.
0131365667 :
Research--Methodology.