Dyfyniad APA

Leedy, P. D., & Ormrod, J. E. (2001). Practical research: Planning and design (7th ed.). Merrill Prentice Hall.

Dyfyniad Arddull Chicago

Leedy, Paul D., and Jeanne Ellis Ormrod. Practical Research: Planning and Design. 7th ed. Upper Saddle River, N.J: Merrill Prentice Hall, 2001.

Dyfyniad MLA

Leedy, Paul D., and Jeanne Ellis Ormrod. Practical Research: Planning and Design. 7th ed. Merrill Prentice Hall, 2001.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.