Gay, L.R. Educational research : competencies for analysis and application / L.R. Gay - 5th. ed - Upper Saddle River, New Jersey : Merril , 1996 - xxiv, 662 p. : il. ; 26 cm ISBN: 0023408146 Subjects--Topical Terms: Educación --- Investigación LC Class. No.: LB 1028 / G39 1996