Present Perfects Compete

@article{schaden09,
    author = "Schaden, Gerhard",
    title = "Present {P}erfects {C}ompete",
    journal = "Linguistics and Philosophy",
    volume = "32",
    pages = "115--141",
    year = "2009",
    DOI = "10.1007/s10988-009-9056-3",
    annote = ""
}