@book { ConceptualIssuesinEnvironmentalEducation,
    title = "Conceptual Issues in Environmental Education",
    author = "Shoshana Helen {Keiny} and Uri {Zoller}",
    year = "1991",
    publisher = "Peter Lang Verlag",
    address = "New York, United States of America",
    url = "https://www.peterlang.com/document/1081989"
}