@article{10_4153_CJM_1969_088_3,
     author = {Bender, Edward A. and Tucker, Thomas W.},
     title = {The {Exponents} of {Strongly} {Connected} {Graphs}},
     journal = {Canadian journal of mathematics},
     pages = {769--782},
     year = {1969},
     volume = {21},
     number = {1},
     doi = {10.4153/CJM-1969-088-3},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1969-088-3/}
}