@article{10_4153_CJM_1981_110_3,
     author = {Kofner, Jacob},
     title = {Transitivity and {Ortho-Bases}},
     journal = {Canadian journal of mathematics},
     pages = {1439--1447},
     year = {1981},
     volume = {33},
     number = {6},
     doi = {10.4153/CJM-1981-110-3},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1981-110-3/}
}