@book { LevelofUseandEffectivenessofsomeSelectMethodofTeachingEconomicsinSecondarySchools,
    title = "Level of Use and Effectiveness of some Select Method of Teaching Economics in Secondary Schools",
    author = "Serena {Smith}",
    year = "2011",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656005506",
    url = "https://www.hausarbeiten.de/document/178382"
}