Leedy, Paul D. Practical research : planning and design / Paul D. Leedy, Jeanne Ellis Ormrod - 10th ed ; New international ed. - Harlow, Essex : Pearson Education, 2014 - ii, 374 p. : ill. ; 28 cm. Includes bibliographical references and index ISBN: 978129021171 Subjects--Topical Terms: Research--Methodology