@article{10_4153_CJM_1968_151_x,
     author = {Miller, Donald J.},
     title = {The {Categorical} {Product} of {Graphs}},
     journal = {Canadian journal of mathematics},
     pages = {1511--1521},
     year = {1968},
     volume = {20},
     number = {1},
     doi = {10.4153/CJM-1968-151-x},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1968-151-x/}
}