@Article{Dar90,
    Author       = "Darmochwa{\l}, A.",
    Year         = "1990",
    Title        = "{Families of Subsets, Subspaces and Mappings in
                    Topological Spaces}",
    Journal      = "Journal of Formalized Mathematics",
    Volume       = "1",
    Number       = "2",
    Pages        = "257-261",
    Comment      = "TPTPRef"
}

@Article{Dar90,
    Author       = "Darmochwa{\l}, A.",
    Year         = "1989",
    Title        = "{Finite Sets}",
    Journal      = "Journal of Formalized Mathematics",
    Volume       = "1",
    Number       = "1",
    Pages        = "165-167",
    Comment      = "TPTPRef"
}

@Article{Dar90,
    Author       = "Darmochwa{\l}, A.",
    Year         = "1990",
    Title        = "{Compact Spaces}",
    Journal      = "Journal of Formalized Mathematics",
    Volume       = "1",
    Number       = "2",
    Pages        = "383-386",
    Comment      = "TPTPRef"
}