@article{ASNSP_1948_2_13_1-4_51_0,
     author = {Fejes, L\'aszl\'o},
     title = {\"Uber einige Extremaleigenschaften der regul\"aren Polyeder und des gleichseitigen Dreiecksgitters},
     journal = {Annali della Scuola Normale Superiore di Pisa - Classe di Scienze},
     pages = {51--58},
     publisher = {Scuola normale superiore},
     volume = {Ser. 2, 13},
     number = {1-4},
     year = {1948},
     zbl = {0030.22102},
     mrnumber = {24156},
     language = {de},
     url = {http://www.numdam.org/item/ASNSP_1948_2_13_1-4_51_0/}
}

Fejes, László. Über einige Extremaleigenschaften der regulären Polyeder und des gleichseitigen Dreiecksgitters. Annali della Scuola Normale Superiore di Pisa - Classe di Scienze, Série 2, Tome 13 (1948) no. 1-4, pp. 51-58. http://www.numdam.org/item/ASNSP_1948_2_13_1-4_51_0/