Hedrick, T. E., Bickman, L., & Rog, D. J. (1993). Applied research design: A practical guide. Sage Publications.
Chicago Style aipamenaHedrick, Terry E., Leonard Bickman, and Debra J. Rog. Applied Research Design: A Practical Guide. Newbury Park: Sage Publications, 1993.
MLA aipamenaHedrick, Terry E., et al. Applied Research Design: A Practical Guide. Sage Publications, 1993.
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