@article{CMJ_2006_56_3_a15,
     author = {Shao, Yanling and Sun, Liang and Gao, Yubin},
     title = {$\pm$ sign pattern matrices that allow orthogonality},
     journal = {Czechoslovak Mathematical Journal},
     pages = {969--979},
     year = {2006},
     volume = {56},
     number = {3},
     mrnumber = {2261669},
     zbl = {1164.15327},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2006_56_3_a15/}
}