Gaya APA
Fraenkel, J, R., Wallen, N, E. (1990).
In Education .
UnitetStates of Amerika:
McGraw-Hill Publishing Company.
Gaya MLA
Fraenkel, Jack, R.., Wallen, Norman, E..
"In Education".
UnitetStates of Amerika:
McGraw-Hill Publishing Company,
1990.
Textbook.