@book {IOPORT.06118259,
    author       = {Heinrich, Gert},
    title        = {Operations research. 2nd ed.},
    year         = {2013},
    isbn         = {978-3-486-71696-2},
    edition      = {2nd ed.},
    pages        = {xi, 197~p.},
    publisher    = {M\"unchen: Oldenbourg Verlag},
    identifier   = {06118259},
}