@article{10_37236_1256,
     author = {J. B. M. Melissen and P. C. Schuur},
     title = {Improved coverings of a square with six and eight equal circles},
     journal = {The electronic journal of combinatorics},
     year = {1996},
     volume = {3},
     number = {1},
     doi = {10.37236/1256},
     zbl = {0889.52020},
     url = {http://geodesic.mathdoc.fr/articles/10.37236/1256/}
}