@article{10_4153_CJM_1966_058_8,
     author = {DeMar, Richard F.},
     title = {Uniqueness {Classes} for {Difference} {Functionals}},
     journal = {Canadian journal of mathematics},
     pages = {593--607},
     year = {1966},
     volume = {18},
     number = {1},
     doi = {10.4153/CJM-1966-058-8},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1966-058-8/}
}