@article{10_4064_ap_23_1_65_72,
     author = {S. Topa},
     title = {On a generalization of the functional equation for the harmonic ratio of four points on a projective line over an arbitrary commutative field},
     journal = {Annales Polonici Mathematici},
     pages = {65--72},
     publisher = {mathdoc},
     volume = {23},
     number = {1},
     year = {1970},
     doi = {10.4064/ap-23-1-65-72},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/ap-23-1-65-72/}
}