Gaya APA
dkk., L, K. (2008).
Happy Lesson Volume 1 Workbook Part A for Elementary Student Year 1-3 .
Bandung:
Tinta Emas Publishing.
Gaya MLA
dkk., Lia, Kurniawaty,.
"Happy Lesson Volume 1 Workbook Part A for Elementary Student Year 1-3".
Bandung:
Tinta Emas Publishing,
2008.
Text.