Gaya APA
Spencer, J, F. (2007).
Science month by month, grades 3-8: practical ideas and activities for teachers and homeschoolers .
:
John Wiley n Sons.
Gaya MLA
Spencer, Julia, Farish.
"Science month by month, grades 3-8: practical ideas and activities for teachers and homeschoolers".
:
John Wiley n Sons,
2007.
Textbook.