Dyfyniad APA

Leedy, P. D., & Ormrod, J. E. (2018). Practical research: Planning and design (11th ed.). Pearson.

Dyfyniad Arddull Chicago

Leedy, Paul D., and Jeanne Ellis Ormrod. Practical Research: Planning and Design. 11th ed. Noida: Pearson, 2018.

Dyfyniad MLA

Leedy, Paul D., and Jeanne Ellis Ormrod. Practical Research: Planning and Design. 11th ed. Pearson, 2018.

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