@article{10_1017_S0017089500009629,
     author = {Kiventidis, Thomas},
     title = {Positive solutions of integrodifferential and difference equations with unbounded delay},
     journal = {Glasgow mathematical journal},
     pages = {105--113},
     year = {1993},
     volume = {35},
     number = {1},
     doi = {10.1017/S0017089500009629},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500009629/}
}