@article{10_1017_S0017089500001774,
     author = {Kopp, P. E.},
     title = {A ratio limit theorem for contraction projections and applications},
     journal = {Glasgow mathematical journal},
     pages = {80--85},
     year = {1973},
     volume = {14},
     number = {1},
     doi = {10.1017/S0017089500001774},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500001774/}
}