@book { RealOptionValuationofProductInnovation,
    title = "Real Option Valuation of Product Innovation",
    author = "Yuanyun {Kang}",
    year = "2009",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836624718",
    url = "https://m.diplom.de/document/226468"
}