@article{10_1017_S0017089500001828,
     author = {Klotz, W.},
     title = {Arithmetic progressions in finite sets of real numbers},
     journal = {Glasgow mathematical journal},
     pages = {101--104},
     year = {1973},
     volume = {14},
     number = {2},
     doi = {10.1017/S0017089500001828},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500001828/}
}