Gaya APA
Maggs, M. (1978).
Programmed English : A Self-Instructional Course Book 1 (Cetakan 1).
New York:
Grolier International, Inc..
Gaya MLA
Maggs, Margaret.
"Programmed English : A Self-Instructional Course Book 1".
Cetakan 1
New York:
Grolier International, Inc.,
1978.
Text.