@book { OilProducingCountriesandOilCompanies,
    title = "Oil Producing Countries and Oil Companies",
    author = "Alain {Beltran}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Bruxelles, Belgium",
    url = "https://www.peterlang.com/document/1107527"
}