APA (7e ed.) Bronvermelding

Ashbrook, P. (2003). Science is simple: Over 250 activities for preschoolers. Gryphon House.

Chicago (17e ed.) Bronvermelding

Ashbrook, Peggy. Science Is Simple: Over 250 Activities for Preschoolers. Beltsville, Md: Gryphon House, 2003.

MLA (9e ed.) Bronvermelding

Ashbrook, Peggy. Science Is Simple: Over 250 Activities for Preschoolers. Gryphon House, 2003.