@article{10_4153_CJM_1972_107_4,
     author = {Cheng, Chao-Kun},
     title = {Multiplications on a {Space} with {Finitely} {Many} {Non-Vanishing} {Homotopy} {Groups}},
     journal = {Canadian journal of mathematics},
     pages = {1052--1062},
     year = {1972},
     volume = {24},
     number = {6},
     doi = {10.4153/CJM-1972-107-4},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1972-107-4/}
}