Heimlich, J. E. (2002). Environmental education: A resource handbook. Phi Delta Kappa EducationalFoundation.
Citazione stile Chigago Style (17a edizione)Heimlich, Joe E. Environmental Education: A Resource Handbook. Estados Unidos: Phi Delta Kappa EducationalFoundation, 2002.
Citatione MLA (9a ed.)Heimlich, Joe E. Environmental Education: A Resource Handbook. Phi Delta Kappa EducationalFoundation, 2002.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.