@article{JRAM_1979__306_152097,
     author = {Horst R. Thieme},
     title = {Asymptotic estimates of the solutions of nonlinear integral equations and asymptotic speeds for the spread of populations.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {94--121},
     publisher = {mathdoc},
     volume = {306},
     year = {1979},
     zbl = {0395.45010},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1979__306_152097/}
}